Recording apparatus, recording method, playback apparatus, playback method, recording/playback apparatus, recording/playback method, presentation medium and recording medium

ABSTRACT

This invention relates to a recording apparatus for recording a plurality of pieces of data into a recording medium is characterized in that the recording apparatus including a specifying means for specifying that a write operation over a combination of the pieces of data is prohibited, a judgment means for forming a judgment on what is specified for a predetermined piece of data by the specifying means in response to a command to perform a recording operation over the piece of data, and a control means for controlling an operation to record the pieces of data into the recording medium in accordance with a result of a judgment formed by the judgment means; and relates to a recording method adopted in a recording apparatus for recording a plurality of pieces of data into a recording medium is characterized in that the recording method including a specifying step of specifying that a write operation over a combination of the pieces of data is prohibited, a judgment step of forming a judgment on what is specified for a predetermined piece of data at the specifying step in response to a command to perform a recording operation over the piece of data, and a control step of controlling an operation to record the pieces of data into the recording medium in accordance with a result of a judgment formed at the judgment step.

This is a divisional of application Ser. No. 09/174,845, filed Oct. 19,1998.

BACKGROUND OF THE INVENTION

In general, the present invention relates to a recording apparatus, arecording method, a playback apparatus, a playback method, arecording/playback apparatus, a recording/playback method, apresentation medium and a recording medium. More particularly, thepresent invention relates to a recording apparatus, a recording method,a playback apparatus, a playback method, a recording/playback apparatus,a recording/playback method, a presentation medium and a recordingmedium offering improved operatability of the recording/playbackapparatus by virtue of a facility for specifying whether or not toprohibit a write operation over for each type of data.

An optical disc can be used for recording a plurality of titles (or aprogram). The user is allowed select a desired title recorded in theoptical disc to be played back.

In addition, the user is also capable of specifying any plurality oftitles which are combined to be played back as a program which comprisesthe same plurality of specified titles.

In the related-art optical-disc apparatus, however, while an overwriteoperation on the optical disc itself or a write operation over any titlecan be prohibited, a write operation over a program for example can notbe prohibited, giving rise to a problem of poor operatability of theoptical-disc apparatus.

In addition, in the related-art disc apparatus, there is also raised aproblem that once titles or a program have been recorded on a disc, theplayback person is capable of playing them back with a high degree offreedom, but the recording person is not capable of controlling datarecorded on the disc in a way adjusted to the person playing back thedata.

SUMMARY OF THE INVENTION

It is thus an object of the present invention addressing the problemsdescribed above to offer improved operatability of an optical-discapparatus by virtue of a facility for specifying whether or not toprohibit a overwrite operation for a combination of pieces of data. Itis fruther an object of the present invention an person recording datais capsble of controlling an operation to play back the data.

In accordance with one aspect of the present invention, there isprovided a recording apparatus for recording a plurality of pieces ofdata into a recording medium is characterized in that the recordingapparatus including a specifying means for specifying that a writeoperation over a combination of the pieces of data is prohibited, ajudgment means for forming a judgment on what is specified for apredetermined piece of data by the specifying means in response to acommand to perform a recording operation over the piece of data, and acontrol means for controlling an operation to record the pieces of datainto the recording medium in accordance with a result of a judgmentformed by the judgment means.

In accordance with another aspect of the present invention, there isprovided a recording method adopted in a recording apparatus forrecording a plurality of pieces of data into a recording medium ischaracterized in that the recording method including a specifying stepof specifying that a write operation over a combination of the pieces ofdata is prohibited, a judgment step of forming a judgment on what isspecified for a predetermined piece of data at the specifying step inresponse to a command to perform a recording operation over the piece ofdata, and a control step of controlling an operation to record thepieces of data into the recording medium in accordance with a result ofa judgment formed at the judgment step.

In accordance with further aspect of the present invention, there isprovided a presentation medium is characterized in that the presentationmedium is used for presenting a program readable by a computer forexecution to make a recording apparatus for recording a plurality ofpieces of data into a recording medium carry out processing including aspecifying step of specifying that a write operation over a combinationof the pieces of data is prohibited, a judgment step of forming ajudgment on what is specified for a predetermined piece of data at thespecifying step in response to a command to perform a recordingoperation over the piece of data, and a control step of controlling anoperation to record the pieces of data into the recording medium inaccordance with a result of a judgment formed at the judgment step.

In accordance with still further aspect of the present invention, thereis provided a recording medium for recording a plurality of pieces ofdata is characterized in that the recording medium is also used forrecording specifying information for specifying that a write operationover a combination of the pieces of data is prohibited.

In accordance with yet further aspect of the present invention, there isprovided a recording/playback apparatus for recording and playing back aplurality of pieces of data into and from a recording medium ischaracterized in that the recording/playback apparatus including arecording means for recording specifying information stating prohibitionof an overwrite operation for a combination of the pieces of data intothe recording medium, a playback means for playing back the specifyinginformation for a piece of data subjected to a recording operation inaccordance with a command from the recording medium, a judgment meansfor forming a judgment on the specifying information played back by theplayback means, and a control means for controlling an operation torecord the piece of data into the recording medium in accordance with aresult of a judgment formed by the judgment means.

In accordance with yet aspect of the present invention, there isprovided a recording/playback method adopted in a recording/playbackapparatus for recording and playing back a plurality of pieces of datainto and from a recording medium is characterized in that therecording/playback method including a recording step of recordingspecifying information stating prohibition of an overwrite operation fora combination of the pieces of data into the recording medium, aplayback step of playing back the specifying information for a piece ofdata subjected to a recording operation in accordance with a commandfrom the recording medium, a judgment step of forming a judgment on thespecifying information played back at the playback step, and a controlstep of controlling an operation to record the piece of data into therecording medium in accordance with a result of a judgment formed at thejudgment step.

In accordance with yet aspect of the present invention, there isprovided a presentation medium is characterized in that the presentationmedium is used for presenting a program readable by a computer forexecution to make a recording/playback apparatus for recording andplaying back a plurality of pieces of data into and from a recordingmedium carry out processing including a recording step of recordingspecifying information stating prohibition of an overwrite operation fora combination of the pieces of data into the recording medium, aplayback step of playing back the specifying information for a piece ofdata subjected to a recording operation in accordance with a commandfrom the recording medium, a judgment step of forming a judgment on thespecifying information played back at the playback step, and a controlstep of controlling an operation to record the piece of data into therecording medium in accordance with a result of a judgment formed at thejudgment step.

In accordance with yet aspect of the present invention, there isprovided a playback apparatus for playing back data from a recordingmedium is characterized in the playback apparatus including a specifyingmeans for specifying whether or not an operation to play back datarecorded in the recording medium is allowed, a judgment means forforming a judgment on what is specified by the specifying means, and acontrol means for controlling an operation to play back data from therecording medium in accordance with a result of a judgment formed by thejudgment means.

In accordance with yet aspect of the present invention, there isprovided a playback method adopted in a playback apparatus for playingback data from a recording medium is characterized in that the playbackmethod including a specifying step of specifying whether or notoperation to play back data recorded in the recording medium is allowed,a judgment step of forming a judgment on what is specified at thespecifying step, and a control step of controlling an operation to playback data from the recording medium in accordance with a result of ajudgment formed at the judgment step.

In accordance with yet aspect of the present invention, there isprovided a presentation medium is characterized in that the presentationmedium is used for presenting a program readable by a computer forexecution to make a playback apparatus for playing back data from arecording medium carry out processing including a specifying step ofspecifying whether or not an operation to play back data recorded in therecording medium is allowed, a judgment step of forming a judgment onwhat is specified at the specifying step, and a control step ofcontrolling an operation to play back data from the recording medium inaccordance with a result of a judgment formed at the judgment step.

In accordance with yet aspect of the present invention, there isprovided a recording medium for recording data is characterized in thatthe recording medium is also used for recording specifying informationfor specifying whether or not an operation to play back the data isprohibited.

In accordance with yet aspect of the present invention, there isprovided a recording apparatus for recording data into a recordingmedium is characterized in that the recording apparatus including aspecifying means for specifying whether or not an operation to play backdata from the recording medium is prohibited and a recording means forrecording what is specified by the specifying means into the recordingmedium.

In accordance with yet aspect of the present invention, there isprovided a recording method adopted in a recording apparatus forrecording data into a recording medium is characterized in that therecording method including a specifying step of specifying whether ornot an operation to play back data from the recording medium isprohibited and a recording step of recording what is specified at thespecifying step into the recording medium.

In accordance with yet aspect of the present invention, there isprovided a presentation medium is characterized in that the presentationmedium is used for presenting a program readable by a computer forexecution to make a recording apparatus for recording data into arecording medium carry out processing including a specifying step ofspecifying whether or not an operation to play back data from therecording medium is prohibited and a recording step of recording what isspecified at the specifying step into the recording medium.

In accordance with yet aspect of the present invention, there isprovided a recording/playback apparatus for recording and playing backdata into and from a recording medium is characterized in that therecording/playback apparatus including a recording means for recordingspecifying information specifying whether or not to prohibit anoperation to play back data recorded in the recording medium into therecording medium, a playback means for playing back the specifyinginformation for data subjected to a playback operation in accordancewith a command from the recording medium, a judgment means for forming ajudgment on the specifying information played back by the playbackmeans, and a control means for controlling an operation to play backdata from the recording medium in accordance with a result of a judgmentformed by the judgment means.

In accordance with yet aspect of the present invention, there isprovided a recording/playback method adopted in a recording/playbackapparatus for recording and playing back data into and from a recordingmedium is characterized in that the recording/playback method includinga recording step of recording specifying information specifying whetheror not to prohibit an operation to play back data recorded in therecording medium into the recording medium, a playback step of playingback the specifying information for data subjected to a playbackoperation in accordance with a command from the recording medium, ajudgment step of forming a judgment on the specifying information playedback at the playback step, and a control step of controlling anoperation to play back data from the recording medium in accordance witha result of a judgment formed at the judgment step.

In accordance with yet aspect of the present invention, there isprovided a presentation medium is characterized in that the presentationmedium is used for presenting a program readable by a computer forexecution to make a recording/playback apparatus for recording andplaying back data into and from a recording medium carry out processingincluding a recording step of recording specifying informationspecifying whether or not to prohibit an operation to play back datarecorded in the recording medium into the recording medium, a playbackstep of playing back the specifying information for data subjected to aplayback operation in accordance with a command from the recordingmedium, a judgment step of forming a judgment on the specifyinginformation played back at the playback step, and a control step ofcontrolling an operation to play back data from the recording medium inaccordance with a result of a judgment formed at the judgment step.

In the recording apparatus, the recording method, the presentationmedium and the recording medium according to the present invention,prohibition of a write operation over a combination of pieces of data isspecified.

In the recording/playback apparatus, the recording/playback method andthe presentation medium according to the present invention, specifyinginformation stating prohibition of an overwrite operation for acombination of pieces of data is recorded into a recording medium, thespecifying information for a piece of data subjected to a recordingoperation in accordance with a command is played back from the recordingmedium, and an operation to record the piece of data into the recordingmedium is controlled in accordance with a result of a judgment formed onthe specifying information played back from the recording medium.

In the playback apparatus, the recording playback method and thepresentation medium according to the present invention, an operation toplay back data from a recording medium is controlled in accordance witha prescribed regulation as to whether or not the operation to play backthe data recorded in the recording medium is allowed.

A recording medium according to the present invention is also used forrecording specifying information for specifying whether or not anoperation to play back the data is prohibited.

In the recording apparatus, the recording method and the presentationmedium according to the present invention, a prescribed regulation as towhether or not to prohibit an operation to play back data recorded in arecording medium is recorded in the recording medium.

In the recording/playback apparatus, the recording/playback method andthe presentation medium according to the present invention, specifyinginformation specifying whether or not to prohibit an operation to playback data recorded in a recording medium is recorded into the recordingmedium, the specifying information for data subjected to a playbackoperation in accordance with a command is played back from the recordingmedium, and an operation to play back data from the recording medium iscontrolled in accordance with a result of a judgment formed on thespecifying information played back from the recording medium.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an explanatory diagram used for describing an organization ofdirectories;

FIG. 2 is an explanatory diagram used for describing the structure of aVOLUME.TOC file;

FIG. 3 is an explanatory diagram used for describing the structure ofvolume_information ( );

FIG. 4 is an explanatory diagram used for describing the structure ofvolume_attribute ( );

FIG. 5 is an explanatory diagram used for describing the structure ofresume ( );

FIG. 6 is an explanatory diagram used for describing the structure ofvolume_rating ( );

FIG. 7 is an explanatory diagram used for describing the structure ofwrite_protect ( );

FIG. 8 is an explanatory diagram used for describing the structure ofplay_protect ( );

FIG. 9 is an explanatory diagram used for describing the structure ofrecording_timer ( );

FIG. 10 is an explanatory diagram used for describing the structure oftext_block ( );

FIG. 11 is an explanatory diagram used for describing the structure oflanguage_set ( );

FIG. 12 is an explanatory diagram used for describing the structure oftext_item ( );

FIG. 13 is an explanatory diagram used for describing the structure ofALBUM.STR;

FIG. 14 is an explanatory diagram used for describing the structure ofalbum ( );

FIG. 15 is an explanatory diagram used for describing the structure ofTITLE_###.VDR;

FIG. 16 is an explanatory diagram used for describing the structure oftitle_info ( );

FIG. 17 is an explanatory diagram used for describing the structure ofPROGRAM_$$$.PGI;

FIG. 18 is an explanatory diagram used for describing the structure ofprogram ( );

FIG. 19 is an explanatory diagram used for describing the structure ofplay_list ( );

FIG. 20 is an explanatory diagram used for describing the structure ofplay_item ( );

FIG. 21 is an explanatory diagram used for describing the structure ofCHUNKGROUP_###.CGIT;

FIG. 22 is an explanatory diagram used for describing the structure ofchunk_connection_info ( );

FIG. 23 is an explanatory diagram used for describing the structure ofchunk_arrangement_info ( );

FIG. 24 is an explanatory diagram used for describing the structure ofCHUNK_%%%.ABST;

FIGS. 25A and 25B are block diagrams showing a typical configuration ofan optical-disc apparatus to which the present invention is applied;

FIG. 26 is an explanatory diagram used for describing an organization ofdirectories;

FIG. 27 is an explanatory diagram used for describing a logicalorganization of directories;

FIG. 28 is an explanatory diagram used for describing an offset;

FIG. 29 is an explanatory diagram used for describing an organization ofdirectories;

FIG. 30 is an explanatory diagram used for describing an organization ofdirectories;

FIG. 31 is an explanatory diagram used for describing a logicalorganization of directories;

FIG. 32 is an explanatory diagram used for describing an organization ofdirectories;

FIG. 33 is an explanatory diagram used for describing an organization ofdirectories;

FIG. 34 is an explanatory diagram used for describing a logicalorganization of directories;

FIG. 35 is an explanatory diagram used for describing a logicalorganization of directories;

FIG. 36 is an explanatory diagram used for describingvolume_write_level;

FIG. 37 is a flowchart representing processing to modify write_protect;

FIGS. 38A and 38B are flowcharts representing recording processing;

FIG. 39 is a continuation of the flowchart representing recordingprocessing shown in FIG. 38;

FIG. 40 is an explanatory diagram used for describing a relation ofvolume_write_protect_level;

FIG. 41 is an explanatory diagram used for describingvolume_play_protect_flag;

FIG. 42 is a flowchart representing processing to modify play_protect;

FIGS. 43A and 43B are flowcharts representing playback processing;

FIGS. 44A and 44B are flowcharts representing other playback processing;

FIG. 45 is an explanatory diagram used for describingvolume_rating_type;

FIG. 46 is an explanatory diagram used for describing CARA_category;

FIG. 47 is an explanatory diagram used for describing RSAC_category;

FIG. 48 is an explanatory diagram used for describing RSAC level;

FIGS. 49A and 49B are flowcharts representing processing to modifyvolume_rating;

FIGS. 50A and 50B are flowcharts representing processing to executevolume_rating; and

FIGS. 51A and 51B and 51C are flowcharts representing a continuation ofthe processing to execute volume_rating shown in FIG. 50.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Before embodiments of the present invention are described, each meanscited in claims of the patent in the specification is exemplified by atypical implementation appended after the means by enclosing theimplementation in parentheses in the following description ofcharacteristics of the present invention in order to clarify a relationassociating the means with the implementation. It is needless to say,however, that the appended implementation is not to intended to beconstrued in a limiting sense, that is, examples of the means are notlimited to the appended implementation.

According to claim 1, a recording apparatus for recording a plurality ofpieces of data into a recording medium is characterized in that therecording apparatus comprises:

a specifying means (implemented typically by flags_for_program shown inFIG. 18) for specifying that a write operation over a combination of thepieces of data is prohibited;

a judgment means (implemented typically by steps S26 and S35 of aflowchart shown in FIG. 38) for forming a judgment on what is specifiedfor a predetermined piece of data by the specifying means in response toa command to perform a recording operation over the piece of data; and

a control means (implemented typically by steps S30 and S32 of theflowchart shown in FIG. 38) for controlling an operation to record thepieces of data into the recording medium in accordance with a result ofa judgment formed by the judgment means.

According to claim 9, a recording/playback apparatus for recording andplaying back a plurality of pieces of data into and from a recordingmedium is characterized in that the recording/playback apparatuscomprises:

a recording means (implemented typically by a step S10 of a flowchartshown in FIG. 37) for recording specifying information (implementedtypically by flags_for_program shown in FIG. 18) stating prohibition ofan overwrite operation for a combination of the pieces of data into therecording medium;

a playback means (implemented typically by a step S21 of the flowchartshown in FIG. 38) for playing back the specifying information for apiece of data subjected to a recording operation in accordance with acommand from the recording medium;

a judgment means (implemented typically by the steps S26 and S35 of theflowchart shown in FIG. 38) for forming a judgment on the specifyinginformation played back by the playback means; and

a control means (implemented typically by the steps S30 and S32 of theflowchart shown in FIG. 38) for controlling an operation to record thepiece of data into the recording medium in accordance with a result of ajudgment formed by the judgment means.

According to claim 12, a playback apparatus for playing back data from arecording medium is characterized in the playback apparatus comprises:

a specifying means (implemented typically by play_protect shown in FIG.8) for specifying whether or not an operation to play back data recordedin the recording medium is allowed;

a judgment means (implemented typically by steps S72 to S75 of aflowchart shown in FIG. 43) for forming a judgment on what is specifiedby the specifying means; and

a control means (implemented typically by steps S77 and S79 of theflowchart shown in FIG. 43) for controlling an operation to play backdata from the recording medium in accordance with a result of a judgmentformed by the judgment means.

According to claim 17, a recording apparatus for recording data into arecording medium is characterized in that the recording apparatuscomprises:

a specifying means (implemented typically by play_protect ( ) shown inFIG. 8) for specifying whether or not an operation to play back datafrom the recording medium is prohibited; and

a recording means (implemented typically by a step S60 of a flowchartshown in FIG. 42) for recording what is specified by the specifyingmeans into the recording medium.

According to claim 20, a recording/playback apparatus for recording andplaying back data into and from a recording medium is characterized inthat the recording/playback apparatus comprises:

a recording means (implemented typically by the step S60 of theflowchart shown in FIG. 42) for recording specifying information(implemented typically by play_protect shown in FIG. 8) specifyingwhether or not to prohibit an operation to play back data recorded inthe recording medium into the recording medium;

a playback means (implemented typically by a step S71 of the flowchartshown in FIG. 43) for playing back the specifying information for datasubjected to a playback operation in accordance with a command from therecording medium;

a judgment means (implemented typically by the steps S72 to S75 of theflowchart shown in FIG. 43) for forming a judgment on the specifyinginformation played back by the playback means; and

a control means (implemented typically by the steps S77 and S79 of theflowchart shown in FIG. 43) for controlling an operation to play backdata from the recording medium in accordance with a result of a judgmentformed by the judgment means.

The description begins with an explanation of a layout of files on arecording medium provided by the present invention, which information isrecorded into and played back from. Recorded on the recording medium,files shown in FIG. 1 are classified into 7 types listed below.

VOLUME.TOC

ALBUM.STR

PROGRAM_$$$.PGI

TITLE_###.VDR

CHUNKGROUP_@@@.CGIT

CHUNK_%%%%.ABST

CHUNK_%%%%.MPEG2

The VOLUME.TOC and ALBUM.STR files are placed in a root directory. Adirectory named “PROGRAM” is placed immediately below the rootdirectory. The PROGRAM directory includes PROGRAM_$$.PGI files wherenotation $$$ represents the number of a program. By the same token, adirectory named TITLE is placed immediately below the root directory.The TITLE directory includes TITLE_###.VDR files where notation ###represent the number of a title. Placed immediately below the rootdirectory, a CHUNKGROUP directory includes CHUNKGROUP_@@@.CGIT fileswhere notation @@@ represents the number of a chunk group and a CHUNKdirectory includes CHUNK_%%%%.ABST files where notation %%%% representsthe number of a chunk.

Also placed immediately below the root directory, an MPEGAV directorycontains a plurality of sub-directories which each includeCHUNK_%%%%.MPEG2 files where %%%% represents the number of a chunk.

Normally, one VOLUME.TOC file exists in the recording medium. In arecording medium with a special structure such as a recording mediumwith a ROM and RAM hybrid structure, however, a plurality of VOLUME.TOCfiles may exist. This VOLUME.TOC file is used for showing the propertyof the recording medium as a whole.

FIG. 2 is a diagram showing the structure of the VOLUME.TOC file. Asshown in the figure, file_type_id is placed at the head of the file toindicate that the file is a VOLUME.TOC file. file_type_id is followed byvolume_information ( ) which is finally followed by text block ( ).

FIG. 3 is a diagram showing the structure of volume_information ( ). Asshown in the figure, volume_information ( ) comprises volume attribute (), resume ( ), volume_rating ( ), write_protect ( ), play_protect ( )and recording_timer ( ).

volume_attribute ( ) is an area used for recording attributes of thelogical volume. FIG. 4 is a diagram showing a detailed structure ofvolume_attribute ( ). As shown in the figure, volume_attribute ( )includes title_playback_mode_flag and program_playback_mode_flag.

resume ( ) is an area used for recording information used in restorationof a state immediately prior to an eject operation at the time therecording medium is reinserted. FIG. 5 is a diagram showing a detailedstructure of resume ( ).

volume_rating ( ) shown in FIG. 3 is an area used for recordinginformation used in implementation of age limitation ofwatchers/listeners of the volume as a whole in accordance with user agesand user categories. FIG. 6 is a diagram showing a detailed structure ofvolume_rating ( ).

write_protect ( ) shown in FIG. 3 is an area used for recordinginformation used in limitation of operations to change and delete atitle or a program. FIG. 7 is a diagram showing a detailed structure ofwrite_protect ( ).

play_protect ( ) shown in FIG. 3 is an area used for recordinginformation setting a playback enable function or a playback disablefunction and limiting the number of playback operations for a title or aprogram recorded in the volume. FIG. 8 is a diagram showing a detailedstructure of play_protect ( ).

recording_timer ( ) shown in FIG. 3 is an area used for recordinginformation controlling a recording time. FIG. 9 is a diagram showing adetailed structure of recording_timer ( ).

FIG. 10 is a diagram showing a detailed structure of text_block ( ) ofthe VOLUME.TOC file shown in FIG. 2. As shown in FIG. 10, text_block ( )includes language_sets ( ) and text_items ( ). FIGS. 11 and 12 showdetailed structures of language_set ( ) and text_item respectively.

Normally, one ALBUM.STR file shown in FIG. 1 exists in a recordingmedium. In a recording medium with a special structure such as arecording medium with a ROM and RAM hybrid structure, however, aplurality of ALBUM.STR files may exist. The ALBUM.STR file is used forcombining a plurality of recording media into a configuration that makesthe recording media appear as if there were only a single recordingmedium.

FIG. 13 is a diagram showing the structure of the ALBUM.STR file. Asshown in the figure, file_type_id is placed at the head of the file toindicate that the file is ALBUM.STR. file_type_id is followed by album () which is finally followed by text_block ( ).

album ( ) is an area used for recording information used in handling aplurality of volumes, that is, a plurality of recording media, as oneintegrated volume. FIG. 14 is a diagram showing a detailed structure ofalbum ( ).

As many TITLE_###.VDR files shown in FIG. 1 as titles exist. A titlerefers to, for example, a musical selection in the case of a compactdisc or a program in the case of a television broadcasting. FIG. 15 is adiagram showing the structure of a TITLE_###.VDR file. As shown in thefigure, file_type_id is placed at the head of the file to indicate thatthe file is TITLE_###.VDR. file_type_id is followed by title_info ( )which is finally followed by text_block ( ). Notation ### is a string ofcharacters representing the number of a title.

title_info ( ) is an area used for recording a start point and an endpoint of the title on a chunk group and other attributes of the title.FIG. 16 is a diagram showing a detailed structure of title_info ( ).

As many PROGRAM_$$$.PGI files shown in FIG. 1 as programs exist. Aprogram comprises a plurality of cuts each specifying an area of aportion or all of a title. Cuts of a program are played back in aspecified order. FIG. 17 is a diagram showing the structure of aPROGRAM_$$$.PGI file. As shown in the figure, file_type_id is placed atthe head of the file to indicate that the file is PROGRAM_$$$.PGI.file_type_id is followed by program ( ) which is finally followed bytext_block ( ). Notation $$$ is a string of characters representing thenumber of a program.

program ( ) is an area used for recording information required in anoperation to collect necessary portions of titles and play back themwithout accomplishing irreversible editing of materials. FIG. 18 is adiagram showing a detailed structure of program ( ).

program ( ) shown in FIG. 18 has one play_list. FIG. 19 is a diagramshowing details of play_list ( ).

A plurality of play_items ( ) are placed in play list. FIG. 20 is adiagram showing details of play item ( ).

As many CHUNKGROUP_@@@.CGIT files shown in FIG. 1 as many chunk groupsexist. A chunk group is a data structure used for arranging a bitstream. When the user normally operates an apparatus for recording andplaying back information into and from a recording medium such as a VDR(Video Disc Recorder), the user is not aware of the existence of thisfile.

FIG. 21 is a diagram showing a CHUNKGROUP_@@@.CGIT file. As shown in thefigure, file_type_id is placed at the head of the file to indicate thatthe file is CHUNKGROUP_@@@.CGIT. file_type_id is followed bychunkgroup_time_base_flags and chunkgroup_time_base_offset which arefollowed by chunk_connection_info ( ). Finally, chunk_connection_info () is followed by text_block ( ).

chunkgroup_time_base_flags are flags each associated with a referencecounter of a chunk group. chunkgroup_time_base_offset shows a start timeof a reference time axis of a chunk group. chunkgroup_time_base_offsetis a 32-bit value set in a counter which counts up at a frequency of 90kHz. chunk_connection_info ( ) is an area used for recording peculiarinformation such as a video switch-over point, and video and audiosynchronization. FIG. 22 is a diagram showing a detailed structure ofchunk_connection_info ( ).

chunk_connection_info ( ) includes as many loops ofchunk_arrangement_info ( ) as chunks pertaining to a chunk group. FIG.23 is a diagram showing details of chunk_arrangement_info ( ).

As many CHUNK_%%%%.ABST files shown in FIG. 1 as many chunks exist. Achunk is information file for a stream file. FIG. 24 is a diagramshowing the structure of a CHUNK_%%%%.ABST file. As shown in the figure,file_type_id is placed at the head of the file to indicate that the fileis CHUNK_%%%%.ABST.

The CHUNK_%%%%.MPEG2 file shown in FIG. 1 is a stream file. Unlike otherfiles which are generally used for storing information only, this fileis used for storing an MPEG bit stream.

FIG. 25 is a diagram showing a typical configuration of an optical-discapparatus for recording and playing back information into and from anoptical disc used as a recording medium including the files describedabove. In the optical-disc apparatus, a single optical head 2 isprovided for a rewritable optical disc 1. The optical head 2 is used forboth reading out and writing information from and into the optical disc1.

After being demodulated in an RF & demodulation/modulation circuit 3, abit stream read out by the optical head 2 from the optical disc 1 issubjected to error correction in an ECC circuit 4 before being suppliedto a read-out channel buffer 6 for absorbing a difference between aread-out rate and a decode-processing rate by way of a switch 5. Anoutput of the read-out channel buffer 6 is supplied to a decoder 7. Theread-out channel buffer 6 is designed so that a system controller 13 iscapable of reading and writing the read-out channel buffer 6.

A bit stream output by the read-out channel buffer 6 is decoded by thedecoder 7 which outputs video and audio signals as results of decoding.The video signal output by the decoder 7 is supplied to a synthesiscircuit 8 to be synthesized therein with a video signal generated by anOSD (On Screen Display) control circuit 9. A result of the synthesis isoutput through an output terminal P1 to a display unit be displayed onthe display unit which is not shown in the figure. In the mean time, theaudio signal generated by the decoder 7 is output to a speaker throughan output terminal P2 to be played back in the speaker which is also notshown in the figure.

On the other hand, a video signal input from an input terminal P3 and anaudio signal input from an input terminal P4 are encoded by an encoder10 before being supplied to a write-in channel buffer 11 for absorbing adifference between an encode-processing rate and a write-in rate. Thewrite-in channel buffer 11 is also designed so that the systemcontroller 13 is capable of reading and writing the write-in channelbuffer 11.

Data stored in the write-in channel buffer 11 is read out from thewrite-in channel buffer 11 and supplied to the ECC circuit 4 by way ofthe switch 5. In the ECC circuit 4, an error correction code is added tothe data before the data is supplied to the RF & demodulation/modulationcircuit 3 to be modulated thereby. A signal, strictly speaking, an RFsignal, output by the RF & demodulation/modulation circuit 3 is recordedonto the optical disc 1 by the optical head 2.

An address detecting circuit 12 detects information on an address on atrack on an optical disc 1 subjected to a recording or playbackoperation. The system controller 13 controls operations of componentscomposing the optical-disc apparatus. The system controller 13 comprisesa CPU 21 for executing various kinds of control, a ROM unit 22 forstoring information such as processing programs to be executed by theCPU 21, a RAM unit 23 for temporarily storing information such as dataobtained as a result in the course of processing carried out by the CPU21 and a RAM unit 24 for storing a variety of information files to berecorded or played back into or from the optical disc 1. The CPU 21finely adjusts the position of the optical head 2 on the basis of aresult of detection output by the address detecting circuit 12. The CPU21 also controls switching-over operations of the switch 5. Composed ofa variety of switches and a variety of buttons, an input unit 14 isoperated by the user for entering a variety of commands to theoptical-disc apparatus.

Next, a basic operation to read in data from an information file isexplained. In an operation to read in data from the VOLUME.TOCinformation file, for example, the CPU 21 employed in the systemcontroller 13 first confirms the physical address at which theVOLUME.TOC file is recorded in the optical disc 1 and the length of thefile by using a file-system operation instruction included in aprocessing program in advance. Then, the CPU 21 moves the optical head 2to a read-out position on the basis of information on the address of theVOLUME.TOC file. Subsequently, the CPU 21 sets the optical head 2, theRF & demodulation/modulation circuit 3 and the ECC circuit 4 in aread-out mode and positions the switch 5 on the side of the read-outchannel buffer 6. Furthermore, the CPU 21 finely adjusts the position ofthe optical head 2 before starting a read-out operation by using theoptical head 2. In the read-out operation, contents of the VOLUME.TOCfile are read out by the optical head 2 and demodulated by the RF &demodulation/modulation circuit 3. The output of the RF &demodulation/modulation circuit 3 is subjected to error correction inthe ECC 4 before being stored in the read-out channel buffer 6.

When the amount of data stored in the read-out channel buffer 6 becomesequal to or exceeds the size of the VOLUME.TOC file, the CPU 21 haltsthe read-out operation. Later on, the CPU 21 reads out the data storedin the read-out channel buffer 6 and stores the data in the RAM unit 24.

Next, a basic operation to write data into an information file isexplained by taking the VOLUME.TOC information file as an example. Firstof all, the CPU 21 searches the file system, that is, the optical disc1, for a free area having a size equal to or larger than a VOLUME.TOCfile, into which data is to be written, and confirms the address of thefree area by using a file-system operation instruction included in aprocessing program in advance.

Then, the CPU 21 transfers the VOLUME.TOC file prepared in the RAM unit24 and to be newly written into the optical disc 1 to the write-inchannel buffer 11. The CPU 21 then moves the optical head 2 to awrite-in position on the basis of information on the address of the VOLUME.TOC file. Subsequently, the CPU 21 sets the optical head 2, the RF &demodulation/modulation circuit 3 and the ECC circuit 4 in a write-inmode and positions the switch 5 on the side of the write-in channelbuffer 11. Furthermore, the CPU 21 finely adjusts the position of theoptical head 2 before starting a write-in operation by using the opticalhead 2.

In the write-in operation, the newly prepared contents of the VOLUME.TOCfile are read out from the write-in channel buffer 11 and supplied tothe ECC circuit 4 by way of the switch 5. In the ECC circuit 4, an errorcorrection code is added to the contents before modulation by the RF &demodulation/modulation circuit 3. A signal output by the RF &demodulation/modulation circuit 3 is recorded into the optical disc 1 bythe optical head 2. When the amount of data read out from the write-inchannel buffer 11 and recorded into the optical disc 1 becomes equal toor exceeds the size of the VOLUME.TOC file, the CPU 21 halts thewrite-in operation.

Finally, the CPU 21 rewrites a pointer pointing to the VOLUME.TOC fileon the file system, that is, the optical disc 1, so as to make thepointer point to the newly written position by using a file-systemoperation instruction included in the processing program in advance.

Next, a basic operation to play back a stream is explained by taking aCHUNK_(—)0001.MPEG2 file shown in FIG. 1 as an example. First of all,the CPU 21 employed in the system controller 13 confirms the physicaladdress at which the CHUNK_(—)0001.MPEG2 file is recorded in the opticaldisc 21 and the length of the file by using a file-system operationinstruction included in a processing program in advance. Then, the CPU21 moves the optical head 2 to a read-out position on the basis ofinformation on the address of the CHUNK_(—)0001.MPEG2 file.Subsequently, the CPU 21 sets the optical head 2, the RF &demodulation/modulation circuit 3 and the ECC circuit 4 in a read-outmode and positions the switch 5 on the side of the read-out channelbuffer 6. Furthermore, the CPU 21 finely adjusts the position of theoptical head 2 before starting a read-out operation by using the opticalhead 2.

In the read-out operation, contents of the CHUNK_(—)0001.MPEG2 file readout by the optical head 2 are stored in the read-out channel buffer 6through the RF & demodulation/modulation circuit 3, the ECC circuit 4and the switch 5. The data stored in the read-out channel buffer 6 isoutput to the decoder 7 to be decoded by the decoder 7 which outputsvideo and audio signals as results of decoding. The audio signalgenerated by the decoder 7 is output to the output terminal P2. In themean time, the video signal output by the decoder 7 is supplied to theoutput terminal P1 through the synthesis circuit 8.

When the amount of data read out from the optical disc 1 and decoded bythe decoder 7 to be finally displayed becomes equal to the size of theCHUNK_(—)0001.MPEG2 or when an instruction to halt the read-outoperation is received from the input unit 14, the CPU 21 stops theread-out and decode processing.

Next, a basic operation to record a stream into an information file isexplained by taking the CHUNK_(—)0001.MPEG2 information file as anexample. First of all, the CPU 21 searches the file system, that is, theoptical disc 1, for a free area having a size equal to or larger thanthe CHUNK_(—)0001.MPEG2 file, into which a stream is to be written, andconfirms the address of the free area by using a file-system operationinstruction included in a processing program in advance.

A video signal input from the input terminal P3 and an audio signalinput from the input terminal P4 are encoded by an encoder 10 beforebeing supplied to the write-in channel buffer 11. The CPU 21 then movesthe optical head 2 to a write-in position on the basis of information onthe address of the CHUNK_(—)0001.MPEG2 file. Subsequently, the CPU 21sets the optical head 2, the RF & demodulation/modulation circuit 3 andthe ECC circuit 4 in a write-in mode and positions the switch 5 on theside of the write-in channel buffer 11. Furthermore, the CPU 21 finelyadjusts the position of the optical head 2 before starting a write-inoperation by using the optical head 2. In the write-in operation, thenewly prepared contents of the CHUNK_(—)0001.MPEG2 file are read outfrom the write-in channel buffer 11 and supplied to optical head 2 byway or the switch 5, the ECC circuit 4 and the RF &demodulation/modulation circuit 3. A signal output by the RF &demodulation/modulation circuit 3 is recorded into the optical disc 1 bythe optical head 2.

When the amount of data read out from the write-in channel buffer 11 andrecorded into the optical disc 1 becomes equal to the size of theCHUNK_(—)0001.MPEG2 or when an instruction to halt the write-inoperation is received from the input unit 14, the CPU 21 stops thewrite-in processing. Finally, the CPU 21 rewrites a pointer pointing tothe CHUNK_(—)0001.MPEG2 file on the file system, that is, the opticaldisc 1, so as to make the pointer point to the newly written position byusing a file-system operation instruction included in the processingprogram in advance.

Assume that information and stream files shown in FIG. 26 have beenrecorded in the optical disc 1. In this example, the optical disc 1includes a file named PROGRAM_(—)001.PGI for storing a program. Inaddition, the optical disc 1 also includes three title files namedTITLE_(—)001.VDR, TITLE_(—)002.VDR and TITLE_(—)003.VDR respectively.

Furthermore, the optical disc 1 also includes two chunk-groupinformation files named CHUNKGROUP_(—)001.CGIT andCHUNKGROUP_(—)002.CGIT. On the top of that, the optical disc 1 includesthree stream files named CHUNK_(—)0001.MPEG2, CHUNK_(—)0011.MPEG2 andCHUNK_(—)0012.MPEG2 as well as three information files namedCHUNK_(—)0001.ABST, CHUNK_(—)00011.ABST and CHUNK_(—)0012.ABSTassociated with the CHUNK_(—)0001.MPEG2, CHUNK_(—)0011.MPEG2 andCHUNK_(—)0012.MPEG2 files respectively.

FIG. 27 is a diagram showing the logical structure of the optical disc 1containing the information and stream files shown in FIG. 26. In thisexample, the chunk information files named CHUNK_(—)0001.ABST,CHUNK_0011.ABST and CHUNK_(—)0012.ABST specify the CHUNK_(—)0001.MPEG2,CHUNK_(—)0011.MPEG2 and CHUNK_(—)0012.MPEG2 stream files respectively.To put it concretely, in a chunk_file_id field of each of theCHUNK_%%%%.ABST files shown in FIG. 24, the file ID of the associatedstream file is specified.

In addition, in this example, the chunk-group information file namedCHUNKGROUP_(—)001.CGIT specifies the chunk information file namedCHUNK_(—)0001.ABST whereas the chunk-group information file namedCHUNKGROUP_(—)002.CGIT specifies the chunk information files namedCHUNK_(—)0011.ABST and CHUNK_(—)0012.ABST. To put it concretely, in achunk_info_file id field of chunk_arrangement_info ( ) shown in FIG. 23,a file ID of chunk information is specified. This chunk_arrangement_info( ) is included in a chunk group information file. As manychunk_arrangement_infos ( ) as chunks pertaining to a chunk group existin the data structure. It should be noted that chunk_arrangement_info () shown in FIG. 23 is described in chunk_connection_info ( ) shown inFIG. 22 and this chunk_connection_info is described in theCHUNKGROUP_###.CGIT file shown in FIG. 21.

There is only one chunk_arrangement_info ( ) in CHUNKGROUP_(—)001. Thechunk_info_file id field of this chunk_arrangement_info ( ) specifiesCHUNK_(—)0001. On the other hand, there are two chunk_arrangement_infos( ) in CHUNKGROUP_(—)002. The chunk info file id fields of thesechunk_arrangement_infos ( ) specify CHUNK_(—)0011 and CHUNK_(—)0012respectively. Thus, a chunk group can be used to specify an order inwhich a plurality of chunks are to be played back.

To put it concretely, first of all, an initial value of a timer for thechunk group is determined by chunkgroup_time_base_offset in theCHUNKGROUP_###.CGIT file shown in FIG. 21. Then, when each chunk iscataloged, presentation_start_cg_time_count andpresentattion_end_cg_time_count of chunk_arrangement_info ( ) shown inFIG. 23 are specified.

For example, assume that the time lengths of CHUNK_(—)0011 andCHUNK_(—)0012 are A and B respectively as shown in FIG. 28. In thiscase, presentation_start_cg_count and presentattion_end_cg_count ofCHUNK_(—)0011 are equal to chunkgroup_time_base_offset andchunk_group_time_base_offset+A respectively. On the other hand,presentation_start_cg_count and presentattion_end_cg_count ofCHUNK_(—)0012 are equal to chunk-group_time_base_offset+A andchunk_group_time_base_offset+A+B respectively. By setting the fields inthis way, CHUNKGROUP_(—)002 is defined so that CHUNK_(—)0011 andCHUNK_(—)0012 are played back continuously.

It should be noted that, if the playback time of CHUNK_(—)0011 overlapsthe playback time of CHUNK_(—)0012, one of the playback times can beshifted to eliminate the overlapping. In addition, transition info ( )in chunk_arrangement_info ( ) shown in FIG. 23 is used as a descriptivefield used for specifying a special effect such as a fade-in, a fade-outor a wipe in a transition from one stream to another one.

In the example shown in FIG. 26 (or FIG. 27), the TITLE_(—)001.VDR andTITLE_(—)002.VDR title information files specify theCHUNKGROUP_(—)001.CGIT chunk-group information file whereas theTITLE_(—)003.VDR title information file specifies theCHUNKGROUP_(—)002.CGIT chunk-group information file. To put itconcretely, a cgit_file_id field in title_info ( ) shown in FIG. 16specifies the file ID of the chunk group. In addition, fields namedtitle_start_chunk_group time_stamp and title_end_chunk_group_time_stampare used for specifying a time range in which the title is defined inthe chunk group.

In the example shown in FIG. 27, for example, TITLE_(—)001 andTITLE_(—)002 specify the first and second halves of CHUNKGROUP_(—)001.It should be noted that the division conforms to a request made by theuser and its position is determined arbitrarily by the user instead ofbeing determined in advance. In this example, let the position ofdivision into TITLE_(—)001 and TITLE_(—)002 be set at a locationseparated away from the head of CHUNKGROUP_(—)001 by a distance of A.

TITLE_(—)001 specifies CHUNKGROUP_(—)001 as a chunk group and a starttime of CHUNKGROUP_(—)001 as a start time of the title. As an end timeof the title, a time of a point specified by the user is specified.

That is to say, as title_start_chunk_group_time_stamp of TITLE_(—)001,chunk-group_time_base_offset (the position of the head) ofCHUNKGROUP_(—)001 is set whereas, as title_end_chunk_group_time_stamp ofTITLE_(—)001, a sum of chunk-group_time_base_offset of CHUNKGROUP_(—)001and the distance A is set.

TITLE_(—)002 specifies CHUNKGROUP_(—)001 as a chunk group and a time ofa point specified by the user is specified a start time of the title. Asan end time of the title, an end time of CHUNKGROUP_(—)001 is specified.

That is to say, as title_start_chunk_group_time_stamp of TITLE_(—)002, asum of chunk-group time_base_offset (the position of the head) ofCHUNKGROUP_(—)001 and the distance A is set whereas, as title_end_chunkgroup time stamp of TITLE_(—)002, a sum of chunk-group time_base_offsetof CHUNKGROUP_(—)001 and the length of CHUNKGROUP_(—)001 is set.

TITLE_(—)003 specifies CHUNKGROUP_(—)002 as a chunk group and a starttime of CHUNKGROUP_(—)002 is specified a start time of the title. As anend time of the title, an end time of CHUNKGROUP_(—)002 is specified.

That is to say, as title_start_chunk_group_time_stamp of TITLE_(—)003,chunk-group_time_base_offset (the position of the head) ofCHUNKGROUP_(—)002 is set whereas, as title_end_chunk_group_time_stamp ofTITLE_(—)003, a sum of chunk-group_time_base_offset of CHUNKGROUP_(—)002and the length of CHUNKGROUP_(—)002 is set.

In addition, in this example, the program information file namedPROGRAM_(—)001.PGI specifies that part of TITLE_(—)001 and part ofTITLE_(—)003 be played back in an order the parts are enumerated. To putit concretely, title_number in play_item ( ) shown in FIG. 20 is usedfor specifying a title. Times defined by a title are used for definingstart and end points to extract a cut. A plurality of such cuts aregathered to compose a program.

The following is a description of an append-record operation toadditionally record new information onto the optical disc 1. To put itconcretely, this append-record operation is typically carried out as avideo recording operation or carried out by the user by operating theinput unit 14 to enter a command to perform video real-time recording tothe optical-disc apparatus. In the latter case, a recording button ispressed if the video-recording end time is not known. A button for aone-touch recording function is pressed, however, for a case in whichthe recording end time can be predicted. The one-touch recordingfunction is a function for carrying out video recording for a fixedperiod of time.

The append-record operation is explained by taking timer recording as anexample. In this case, the user of the optical-disc apparatus specifies,among other things, a recording start time, a recording end time, thebit rate of a bit stream and a channel to be recorded in advance. Inaddition, at a point of time the video recording is reserved, theoptical disc 1 is checked in advance to find out whether or not there isleft a free space suited for the bit rate and the length of therecording time.

If another recording operation is carried out on the optical disc 1between a time a reservation is made and a time to execute the reservedvideo recording, it is quite within the bounds of possibility that theconfirmed free space for implementing the reserved video recording atthe specified bit rate can not be allocated any more. In such a case,the CPU 21 either reduces the bit rate to a value smaller than thespecified fore in order to record information for the reserved period oftime, or records information for a period of time as long as possible bykeeping the bit rate unchanged as it is. It is needless to say that theCPU 21 then carries out the recording operation further and, as aninconvenience for the reserved video recording is detected, a messageinforming the user of the inconvenience is issued.

As the start time of the reserved video recording is approaching, theCPU 21 uses an embedded timer and a clock signal to automaticallyrestore the optical-disc apparatus to an operating mode from a sleepmode. Then, the CPU 21 issues a file-system operation instructionincluded in the processing program from the beginning to allocate anarea used for recording a reserved program on the optical disc 1. Thatis to say, first of all, the CPU 21 subtracts the start time from theend time of the reserved recording to find the length of the recordingtime and, then, calculates a product of the length of the recording timeand the bit rate to find the size of the necessary area to be allocatedfor recording the reserved program. In addition to a stream filerequired in the reserved recording, data may need to be stored in aninformation file. To be more specific, when a new title needs to bestored in a title information file, an area has to be allocated on theoptical disc 1 for recording the title information file. If an area witha sufficient size can not be allocated, it is necessary to adopt thecountermeasure technique described above, that is, reduction of the bitrate or carrying out a recording operation only for a period of timecorresponding to the allocated area.

It should be noted that, since a new title is stored in this case, theuser gives a name to a new stream file, strictly speaking, to a newstream file in a new stream directory. Let the name be¥MPEGAV¥STREAM_(—)003¥ CHUNK_(—)0031. That is to say, the name of thestream file is CHUNK_(—)0031.MPEG2 in the STREAM_(—)003 directory underthe MPEGAV directory in the root directory as shown in FIG. 29.

The CPU 21 issues instructions of execution in the recording mode toother components of the optical-disc apparatus. For example, a videosignal received through the input terminal P3 and an audio signalthrough the input terminal P4 from a tuner not shown in the figure areencoded by the encoder 10 and then stored in a write-in channel buffer11. Then, the CPU 21 moves the optical head 2 to a write positiondetermined by information on an address of the area allocated earlier.The CPU 21 then sets the optical head 2, the RF &demodulation/modulation circuit 3 and the ECC circuit 4 in a write-inmode and positions the switch 5 on the side of the write-in channelbuffer 11. After the position of the optical head 2 has been finelyadjusted, a write-in operation using the optical head 2 is started. Atthat time, data to be recorded in a newly provided file namedCHUNK_(—)0031.MPEG2 is read out from the write-in channel buffer 11 tobe recorded onto the optical disc 1 by way of the switch 5, the ECCcircuit 4, the RF & demodulation/modulation circuit 3 and the opticalhead 2.

When one of the following events occurs during the write-in operationdescribed above, the CPU 21 halts the operation.

1 The end time of the reserved video recording is reached.

2 Information can no longer be recorded onto the optical disc 1 due to areason such as an insufficient storage capacity.

3 An instruction to stop the recording operation is received.

Next, by using a file-system operation instruction included in theprocessing program in advance, the CPU 21 updates a pointer pointing toCHUNK_(—)0031.MPEG2 in the file system with a value pointing to alocation at which information has been newly recorded. In addition, theCPU 21 prepares files respectively for chunk information, chunk-groupinformation and title information, gives a name to each of the files andrecords the information into the files. It should be noted that freespaces for recording the files need to be allocated in advance on theoptical disc 1 during the recording operation or at the reservationtime.

As a result, new information files are created typically as shown inFIG. 30. In the figure, files names each with an asterisk mark ‘*’provided on the right side thereof are the names of the files newlycreated in the operation described above.

FIG. 31 is a diagram showing a relation among the newly createdinformation files. As shown in the figure, TITLE_(—)004 specifiesCHUNKGROUP_(—)003 specifying CHUNK_(—)0031 which specifiesSTREAM_(—)0031.

That is to say, a new stream is recorded in an information file asTITLE_(—)004. By using a function of the optical-disc apparatus toverify a title, the user is capable of knowing information such asattributes of TITLE_(—)004. In addition, TITLE_(—)004 can be playedback.

The following is a description of an operation to overwrite/recordinformation on an optical disc 1 like one shown in FIG. 26 (or FIG. 27).Much like an operation to record a signal onto a video tape, anoverwrite-record operation is an operation to record a new program overan existing program already recorded on the optical disc 1, erasing theexisting program.

In the overwrite-record operation, a position to start the operation isimportant. Assume that the user specifies the head of TITLE_(—)001 as aposition to start and overwrite-record operation. In this case, theoverwrite-record operation is carried out by overwriting existinginformation recorded in TITLE_(—)001, TITLE_(—)002 and TITLE_(—)003 inan order they are enumerated. If the overwrite-record operation has notbeen finished even if the end of TITLE_(—)003 is reached, the recordingoperation is continued by allocating a new free area on the optical disc1. If TITLE_(—)002 is specified as a location to start anoverwrite-record operation, information in TITLE_(—)001 will not beoverwritten by the recording operation because TITLE_(—)001 precedes thestart location of the operation.

Assume that timer video recording is carried out by overwriting existinginformation starting with that at the head of TITLE_(—)003. In thiscase, the user of the optical-disc apparatus specifies, among otherthings, a recording start time, a recording end time, the bit rate of abit stream and a channel to be recorded in advance. In addition, thehead of TITLE_(—)003 is specified as a recording start location which isof importance to the overwrite-record operation. Furthermore, also inthis case, at a point of time the video recording is reserved, theexistence of a space suited for the bit rate and the video recordingtime on the optical disc 1 is verified in advance. In the case of anoverwrite-record operation, a sum of the total size of a plurality ofrewritable titles starting from a specified location and free areas onthe optical disc 1 is a recordable space. To be more specific, in thiscase, a sum of the total size of STREAM_(—)0011 and STREAM_(—)0012streams controlled by TITLE_(—)003 and a free area on the optical disc 1is a recordable space.

In a overwrite-record operation, for the recordable space describedabove, there are some items available for selection as to what order thevideo recording is to be actually carried out. As a first conceivableitem of selection, it is possible to select a technique to recordinformation in an order streams are specified in the title. To be morespecific, in this case, it is possible to select a technique wherein thevideo recording is started from the head of STREAM_(—)0011 and, as theend of STREAM_(—)0011 is reached, the recording is continued to the headof STREAM_(—)0012. Then, as the end of STREAM_(—)0012 is reached, thevideo recording is continued to the free space on the optical disc 1. Asanother technique, first of all, the video recording is carried out onthe free area on the optical disc 1 and, at a point of time the freearea is all used up, the recording is continued to an existing stream.

The former technique is excellent in a sense that the technique emulatesa video tape. That is to say, since the recording operation resembles anoperation to record information onto a video tape, the operation ischaracterized in that the user is capable of comprehending the operationwith ease. On the other hand, characterized in that an already recordedstream is erased later, the latter technique is excellent in a sensethat recorded information is protected.

It should be noted that, if another recording operation is carried outon the optical disc 1 between a time a reservation is made and a time toexecute the reserved video recording, it is quite within the bounds ofpossibility that the confirmed free space for implementing the reservedvideo recording at the specified bit rate can not be allocated any more.In such a case, much like the append-record operation described earlier,the CPU 21 either automatically reduces the bit rate to a value smallerthan the specified fore in order to record information for the reservedperiod of time, or records information for a period of time as long aspossible by keeping the bit rate unchanged as it is.

As the start time of the reserved video recording is approaching, theoptical-disc apparatus is restored from a sleep mode to an operatingmode. The CPU 21 allocates all free areas on the optical disc 1. It isneedless to say that there is also a method whereby a free area is notallocated at this point of time but allocated at a point of time such anarea is required. For the sake of explanation simplicity, a requiredarea is allocated prior to the start of recording.

It should be noted that since the size of a required area is known inadvance in timer recording due to the fact that a start time, an endtime and a bit rate are specified, only an area with a required size ora required size plus a certain additional margin can be allocated. Incase it is necessary to record information files such as a case in whicha title information file to be recorded as a new title is requiredduring recording, however, an area with a size sufficient for recordingthe information files needs to be allocated.

A name is given to a new stream file, strictly speaking, a new streamfile in a new stream directory. Let the name be¥MPEGAV¥STREAM_(—)002¥CHUNK_(—)0031. That is to say, the name of thestream file is CHUNK_(—)0031.MPEG2 in the STREAM_(—)002 directory underthe MPEGAV directory in the root directory as shown in FIG. 32.

A video signal received through the input terminal P3 and an audiosignal through the input terminal P4 from a tuner not shown in thefigure are encoded by the encoder 10 and then stored in a write-inchannel buffer 11. Then, the CPU 21 moves the optical head 2 to a writeposition determined by information on an address of the area allocatedearlier. The CPU 21 then sets the optical head 2, the RF &demodulation/modulation circuit 3 and the ECC circuit 4 in a write-inmode and positions the switch 5 on the side of the write-in channelbuffer 11. After the position of the optical head 2 has been finelyadjusted, a write-in operation using the optical head 2 is started. Atthat time, data to be recorded in a newly provided file namedCHUNK_(—)0031.MPEG2 is read out from the write-in channel buffer 11 tobe recorded onto the optical disc 1 by way of the switch 5, the ECCcircuit 4, the RF & demodulation/modulation circuit 3 and the opticalhead 2.

At that time, first of all, the stream file named CHUNK_(—)0011.MPEG2 isrewritten. After the recording has reached the end of the stream filenamed CHUNK_(—)0011.MPEG2, then, the operation is continued to a streamfile named CHUNK_(—)0012.MPEG2 prior to continuation to a stream filenamed CHUNK_(—)0031.MPEG2.

While the processing described above is being carried out, the CPU 21halts the write-in operation at a point of time any one of the 3conditions described earlier is met.

Then, the CPU 21 executes a file-system operation instruction includedin the processing program in advance to update the stream files, chunkinformation, chunk-group information and title information.

By the way, the configuration of files is changed with timingsynchronized to completion of the write-in operation. For example, whenrecording is carried out on the stream file named CHUNK_(—)0031.MPEG2after the write-in operations of the 2 stream files namedCHUNK_(—)0011.MPEG2 and CHUNK_(—)0012.MPEG2 have been completed, theconfiguration of files on the optical disc 1 is changed to one shown inFIG. 33. A file name with an asterisk mark ‘*’ appended on the rightside thereof is the name of a file newly created this time.

FIG. 34 is a diagram showing a relation of files newly created in thisway, that is, files shown in FIG. 33. When compared with that shown inFIG. 31, it is obvious that CHUNK_(—)0031 is added as a chunk includedin CHUNKGROUP_(—)002 specified by TITLE_(—)003 and CHUNK_(—)0031specifies STREAM_(—)0031.

On the other hand, if the overwrite-record operation is completed whiledata is being written into an existing stream file, that is, if theoverwrite-record operation is completed while data is being written intothe stream file named CHUNK_(—)0011.MPEG2 for example, the free areaallocated for the overwrite operation on the stream file namedCHUNK_(—)0031.MPEG2 is released because no data is overwritten into thefile. In this case, special title processing is carried out. To put itin detail, when an overwrite-record operation is started at the head ofTITLE_(—)003 and the operation is completed in the middle of it, thetitle is split. To be more specific, as shown in FIG. 35, newTITLE_(—)003 is assigned to a region between the start position of theoverwrite-record operation and the position of completion whereasTITLE_(—)004 is given to an area following the region, that is, the restof the area to which TITLE_(—)003 is supposed to be assigned originally.

Next, an operation to play back a title is explained. Now, assume thatan optical disc 1 having files shown in FIG. 26 is inserted into theoptical-disc apparatus and a title is then played back from the disc 1.When the optical disc 1 is inserted into the apparatus, first of all,the CPU 21 reads out data from information files on the optical disc 1and stores the data into the RAM unit 24. This processing is carried outby repeating the basic operation to read in data from an informationfile described earlier.

To be more specific, first of all, the CPU 21 reads out data fromVOLUME.TOC and ALBUM.STR. Then, the CPU 21 examines the directory namedTITLE to find out how many files with a name extension “.VDR” exist inthe directory. A file with such a name extension is a file having titleinformation. The number of files is equal to the number of titles. Inthe example shown in FIG. 26, the number of titles is three. Then, theCPU 21 reads out title information from the three files and stores theinformation into the RAM unit 24.

The CPU 21 controls the OSD control circuit 9 to let the OSD controlcircuit 9 generate character information, that is, information on titlesrecorded on the optical disc 1. The character information is synthesizedby the synthesis circuit 8 with a video signal. A result of thesynthesis is then output through the output terminal P1 to be displayedon the display unit. To be more specific, the length and attributes ofeach of the 3 existing titles existing in this example are displayed.The attributes include the name of the title and a date on which thetitle was recorded.

Assume that the user specifies TITLE_(—)002 as a title to be played backfor example. In the information file of TITLE_(—)002, to be morespecific, in the cgit_file_id field of title_info ( ) shown in FIG. 16,a file ID specifying CHUNKGROUP_(—)001 is recorded. The CPU 21 recordsthe file ID and stores CHUNKGROUP_(—)001 in the RAM unit 24.

Then, the CPU 21 examines which CHUNK the start and end times ofTITLE_(—)002 correspond to. The start and end times are recordedrespectively in the title_start_chunk group_time_stamp andtitle_end_chunk_group_time_stamp fields of title_info shown in FIG. 16.The examination is carried out by comparison with information includedin information on a CHUNKGROUP in which their respective chunks havebeen recorded. To be more specific, the examination is done bycomparison with information recorded in the presentation start cg timecount and presentation_end cg_time_count fields ofchunk_arrangement_info ( ) shown in FIG. 23. In this example, the starttime of TITLE_(—)002 is known to be in the midst of CHUNK_(—)0001 asshown in FIG. 27. That is to say, it is obvious that, in order to playback TITLE_(—)002 from the head thereof, the playback operation needs tobe started from the middle of the CHUNK_(—)0001.MPEG2 stream file.

Subsequently, the CPU 21 examines the stream in order to determine whichpart of the stream corresponds to the head of TITLE_(—)002. That is tosay, the CPU 21 computes the magnitude of an offset time (a time stamp)in the stream corresponding to the head of TITLE_(—)002. Next, by usingcharacteristic-point information in the CHUNK file, a playback startpoint corresponding to a point immediately before the start time isidentified. In this way, an offset distance of the playback start pointfrom the head of the file can be confirmed.

Then, by using a file-system operation instruction included in theprocessing program in advance, the CPU 21 confirms a physical address onthe optical disc 1 in which CHUNK_(—)0001.MPEG2 has been recorded andthe length thereof. Further, the offset address of the playback startpoint found earlier is added to this physical address to finally confirmthe address of the playback start point of TITLE_(—)002.

Subsequently, the CPU 21 moves the optical head 2 to a read-out positiondetermined by information on the address of the CHUNK_(—)0001.MPEG2file. The CPU 21 then sets the optical head 2, the RF &demodulation/modulation circuit 3 and the ECC circuit 4 in a read-outmode and positions the switch 5 on the side of the read-out channelbuffer 6. After the position of the optical head 2 has been finelyadjusted, a read-out operation using the optical head 2 is started. Atthat time, data read out from the file named CHUNK_(—)0001.MPEG2 isstored in the readout channel buffer 6.

The data stored in the read-out channel buffer 6 is then output to thedecoder 7 to be decoded thereby. As results of decoding, the decoder 7outputs video and audio signals. At a point of time the amount of thedata read out from the optical disc 1, decoded by the decoder 7 anddisplayed on the display unit becomes equal to the size of theCHUNK_(—)0001.MPEG2 file, the CPU 21 makes the playback operationtransit to TITLE_(—)003. An operation to play back information fromTITLE_(—)003 is carried out in the same way as TITLE_(—)002.

As the operation to play back data from the recorded titles is completedor as an instruction to halt the read-out operation is received, theread-out and decoding processing is terminated.

It should be noted that, when a new disc or a disc with a differentformat is inserted into the optical-disc apparatus as the optical disc1, the CPU 21 makes an attempt to read out VOLUME.TOC and ALBUM.STR fromthe inserted disc. However, these files usually do not exist in thenewly inserted disc. In such a case, that is, in case VOLUME.TOC andALBUM.STR can not be read out, the CPU 21 issues a message to make arequest for an instruction from the user. In response to the message,the user gives an instruction to the CPU 21 to eject the optical disc 1in case the newly inserted disc has a different format, or to initializethe optical disc 1 in case the newly inserted disc is a new disc evenwith the same format. As an alternative, the instruction may cause dataon the newly inserted disc to be recovered by using some methods in casethe data has been destroyed from the disc which has the same format.

Next, write protection is explained more. The case of the optical disc 1is provided with a write-inhibit notch which is shown in none of thefigures. By operating the write-inhibit notch, an operation to writedata over the optical disc 1 can be disabled. In addition to thiswrite-inhibit notch, information on write protection can be recordedinto the optical disc 1 as data. To be more specific, information onwrite protection can be written into write_protect ( ) [shown in FIG. 7]of volume_information ( ) [shown in FIG. 3] of VOLUME.TOC [shown in FIG.2], flags_for_title of title_info ( ) [shown in FIG. 16] ofTITLE-###.VDR [shown in FIG. 15] or flags_for_program of program ( )[shown in FIG. 18] of PROGRAM_$$$.PGI [shown in FIG. 17].

Write protection is further explained by taking write_protect shown inFIG. 7 as an example. write_protect_length of write_protect ( ) shown inFIG. 7 is an area used for recording the length of write_protect ( ). Asshown in FIG. 36, volume_write_protect_level is an area used forrecording information used for setting write protection for all titlesand all programs recorded in the optical disc 1. A level of 0 indicatesthat no write protection is set. That is to say, in the case of a 0level, data can be written over the optical disc 1 freely. On the otherhand, a level of 1 indicates that only volume_write_protect_level can bemodified. A level of 2 indicates that ALBUM.STR and data protected byprotection levels lower than 2 except 0 can be modified. A level of 3indicates that VOLUME.TOC and data protected by protection levels lowerthan 3 except 0 can be modified.

A level of 4 indicates that a program and data protected by protectionlevels lower than 4 except 0 can be modified. A level of 5 indicatesthat a title and data protected by protection levels lower than 5 except0 can be modified. Finally, a level of 6 indicates that a file with anextension .MPEG2, .ABST or .CGIT added to the name thereof as a suffixand data protected by protection levels lower than 6 except 0 can bemodified.

password_enable_flag is a field used for describing a flag indicatingwhether password_for_volume_write_protect to be described later is validor invalid. If the flag indicates that password for volume_write_protectis valid, it is necessary to enter a password matching that recorded inpassword_for_volume_write_protect in order to modify write_protect ( ).By modification of write_protect ( ), creation of new write_protect ( ),modification of existing write_protect ( ) or deletion of existingwrite_protect ( ) is meant. append_only_flag is a field used fordescribing a flag for limiting modification of a range allowed byvolume_write_protect_level to further addition only. If this flag isvalid, already existing information can not be rewritten.

expiration_time_enable_flag is a field used for describing a flagindicating whether write_protect_expiration_time ( ) to be describedlater is valid or invalid. number_of_times_enable flag is a field usedfor describing a flag indicating whether number_of_times to be describedlater is valid or invalid. password_for_volume_write_protect is an areaused for recording a password required for modifying write_protect ( ).

write_protect_set_time ( ) is an area used for recording a time and adate write_protect ( ) was set or modified least recently in terms ofyears, months, days, hours, minutes and seconds which are each expressedin the BCD format. write_protect_expiration_time ( ) is an area used forrecording information on a time and a date showing a term of validity interms of years, months, days, hours, minutes and seconds which are eachexpressed in the BCD format. A term of validity of a password is set inthis area. When the term of validity expires, information onwrite_protect ( ) can be modified by the user without the need for theuser to enter a password. An indefinite term of validity can also beset.

Next, processing to modify write_protect is explained by referring to aflowchart shown in FIG. 37. As shown in the figure, the processingbegins with a step S1 at which the user enters a command to modifywrite_protect by operating the input unit 14. The flow of the processingthen goes on to a step S2 at which the CPU 21 forms a judgment as towhether or not a predetermined password has been recorded inpassword_for_volume_write_protect in write_Protect ( ) ofvolume_information ( ) in VOLUME.TOC stored in the RAM unit 24. Ifpassword_enable_flag is 1 and a valid password has been recorded inpassword_for_volume_write_protect, the flow of the processing proceedsto a step S3 at which the CPU 21 forms a judgment as to whether or notwrite_protect_expiration_time ( ) in write_protect ( ) is still valid atthe present time.

That is to say, the CPU 21 forms a judgment as to whether or not thepresent time is within a term of validity of the password which isrecorded in write_protect_expiration_time ( ). If the outcome of thejudgment indicates that the password is valid, the flow of theprocessing continues to a step S4 at which the CPU 21 controls the OSDcontrol circuit 9 to let a message be generated to request the user toenter a password. The message is output through the synthesis circuit 8and the output terminal P1 to be displayed on the display unit. The flowof the processing then goes on to a step S5 at which the user sees themessage and, in response to this message, the user enters a password byoperating the input unit 14.

Then, the flow of the processing proceeds to a step S6 at which the CPU21 forms a judgment as to whether or not the password entered by theuser at the step S5 is correct, that is, a judgment as to whether or notthe password entered by the user at the step S5 matches the passwordrecorded in password_for_volume_write_protect. If the outcome of thejudgment indicates that the entered password matches the recordedpassword, the flow of the processing continues to a step S8 at which theCPU 21 controls the OSD control circuit 9 to let a message be generatedto indicate that the user is allowed to change write_protect. Themessage is output through the synthesis circuit 8 and the outputterminal P1 to be displayed on the display unit.

The flow of the processing then goes on to a step S9 at which the usersees the message and, in response to this message, the user entersinformation for changing write_protect by operating the input unit 14.After such information has been input, the flow of the processingproceeds to a step S10 at which the CPU 21 updates write_protect inaccordance with the input information. To put it in detail, the CPU 21updates the contents of write_protect stored in the RAM unit 24 andrecords the updated contents into the optical disc 1.

If the outcome of the judgment formed at the step S6 indicates that theentered password does not match the recorded password, on the otherhand, the flow of the processing continues to a step S7 at which the CPU21 controls the OSD control circuit 9 to let a message be generated anddisplayed on the display unit to indicate that the user is not allowedto change write_protect. In this case, the user is not capable ofchanging write_protect and the pieces of processing carried out at thesteps S8 to S10 are skipped.

If the outcome of the judgment formed at the step S2 indicates that nopassword has been recorded in password_for_volume_write_protect or theoutcome of the judgment formed at the step S3 indicates thatwrite_protect_expiration_time ( ) in write_Protect ( ) has expired,indicating that a recorded password is not valid any more at the presenttime, on the other hand, the flow of the processing proceeds to the stepS8 at which the pieces of processing of the step S8 and the subsequentsteps are carried out. In this case, the user is allowed to updatewrite_protect freely.

Next, processing to record predetermined data into the optical disc 1 isexplained by referring to a flowchart shown in FIGS. 38 and 39. Thisprocessing is started when the user enters a command to record thepredetermined data by operating the input unit 14. As shown in FIG. 38,the processing begins with a step S21 at which the CPU 21 executesprocessing to read in volume_write_protect_level of write_protect ( )stored in the RAM unit 24. The flow of the processing then goes on tosteps S22 to S28 to form judgments as to whether or notvolume_write_protect_level is set at a value of 0 to 6 respectively.

To put it in detail, if the outcome of the judgment formed at the stepS22 indicates that volume_write_protect_level is set at 0, the flow ofthe processing proceeds to a step S30 at which the CPU 21 carries outprocessing to record the data in accordance with the command entered bythe user by operating the input unit 14. That is to say, since the valueof volume_write_protect_level indicates that an overwrite operation isnot prohibited, the user is allowed to carry out processing to recorddata freely.

If the outcome of the judgment formed at the step S23 indicates thatvolume_write_protect_level is set at 1, the flow of the processingproceeds to a step S31 at which the CPU 21 forms a judgment as towhether or not the input data is data to be recorded involume_write_protect_level itself. As described before by referring toFIG. 36, a value of volume_write_protect_level equal to 1 indicates thatthe user is allowed to update volume_write_protect_level itself but awrite operation over other data is prohibited. Thus, if the outcome ofthe judgment formed at the step S31 indicates that the input data isdata to be recorded in volume_write_protect_level itself, the flow ofthe processing proceeds to the step S30 at which the CPU 21 carries outprocessing to write the data over volume_write_protect_level. If theoutcome of the judgment formed at the step S31 indicates that the inputdata is not data to be recorded in volume_write_protect_level, on theother hand, the flow of the processing continues to a step S32 at whichthe CPU 21 controls the OSD control circuit 9 to let a messageindicating that that the recording operation is prohibited be generatedand displayed on the display unit.

If the outcome of the judgment formed at the step S24 indicates thatvolume_write_protect_level is set at 2, the flow of the processingproceeds to a step S33 at which the CPU 21 forms a judgment as towhether or not the input data is data to be recorded in ALBUM.STR. Avalue of volume_write_protect_level equal to 2 indicates that the useris allowed to update only ALBUM.STR and volume_write_protect_level, thatis, data at a level lower than ALBUM.STR. Thus, if the outcome of thejudgment formed at the step S33 indicates that the input data is data tobe recorded in ALBUM.STR, the flow of the processing proceeds to thestep S30 at which the CPU 21 carries out processing to write the inputdata over A LBUM.STR. If the outcome of the judgment formed at the stepS33 indicates that the input data is not data to be recorded inALBUM.STR, on the other hand, the flow of the processing proceeds to thestep S31 at which the CPU 21 carries out processing of this step and thesubsequent processing. To put it in detail, if the outcome of thejudgment formed at the step S31 indicates that the input data is data tobe recorded in volume_write_protect_level itself, the recordingoperation is allowed, but if the outcome of the judgment formed at thestep S31 indicates that the input data is not data to be recorded involume_write_protect_level, on the other hand, the recording operationis prohibited.

If the outcome of the judgment formed at the step S25 indicates thatvolume_write_protect_level is set at 3, the flow of the processingproceeds to a step S34 at which the CPU 21 forms a judgment as towhether or not the input data is data to be recorded in VOLUME.TOC. Avalue of volume_write_protect_level equal to 3 indicates that the useris allowed to update only VOLUME.TOC, ALBUM.STR andvolume_write_protect_level. Thus, if the outcome of the judgment formedat the step S34 indicates that the input data is data to be recorded inVOLUME.TOC, the flow of the processing proceeds to the step S30 at whichthe CPU 21 carries out processing to write the input data over existingdata. If the outcome of the judgment formed at the step S34 indicatesthat the input data is not data to be recorded in VOLUME.TOC, on theother hand, the flow of the processing proceeds to the step S33 at whichthe CPU 21 carries out processing of this step and the subsequentprocessing. To put it in detail, if the outcome of the judgment formedat the step S33 indicates that the input data is data to be recorded inALBUM.STR or volume_write_protect_level itself, the recording operationis allowed, but if the outcome of the judgment formed at the step S33indicates that the input data is not data to be recorded in ALBUM.STR orvolume_write_protect_level, on the other hand, the recording operationis prohibited.

If the outcome of the judgment formed at the step S26 indicates thatvolume_write_protect_level is set at 4, the flow of the processingproceeds to a step S35 at which the CPU 21 forms a judgment as towhether or not the input data is data to be recorded in a programinformation file. A value of volume_write_protect_level equal to 4indicates that the user is allowed to update only a program informationfile, VOLUME.TOC, ALBUM.STR and volume_write_protect_level.

Thus, if the outcome of the judgment formed at the step S35 indicatesthat the input data is data to be recorded in a program informationfile, the flow of the processing proceeds to the step S30 at which theCPU 21 carries out processing to write the input data over existingdata. If the outcome of the judgment formed at the step S35 indicatesthat the input data is not data to be recorded in a program informationfile, on the other hand, the flow of the processing proceeds to the stepS34 at which the CPU 21 carries out processing of this step and thesubsequent processing. To put it in detail, if the outcome of thejudgment formed at the step S34 indicates that the input data is data tobe recorded in VOLUME.TOC, ALBUM.STR or volume_write_protect_levelitself, the recording operation is allowed, but if the outcome of thejudgment formed at the step S34 indicates that the input data is notdata to be recorded in VOLUME.TOC, ALBUM.STR orvolume_write_protect_level, on the other hand, the recording operationis prohibited.

If the outcome of the judgment formed at the step S27 indicates thatvolume_write_protect_level is set at 5, the flow of the processingproceeds to a step S36 at which the CPU 21 forms a judgment as towhether or not the input data is data to be recorded in a titleinformation file. A value of volume_write_protect_level equal to 5indicates that the user is allowed to update only a title informationfile, a program information file, VOLUME.TOC, ALBUM.STR andvolume_write_protect_level. Thus, if the outcome of the judgment formedat the step S36 indicates that the input data is data to be recorded ina title information file, the flow of the processing proceeds to thestep S30 at which the CPU 21 carries out processing to write the inputdata over existing data. If the outcome of the judgment formed at thestep S36 indicates that the input data is not data to be recorded in atitle information file, on the other hand, the flow of the processingproceeds to the step S35 at which the CPU 21 carries out processing ofthis step and the subsequent processing. To put it in detail, if theoutcome of the judgment formed at the step S35 indicates that the inputdata is data to be recorded in a program information file, VOLUME.TOC,ALBUM.STR or volume_write_protect_level itself, the recording operationis allowed, but if the outcome of the judgment formed at the step S35indicates that the input data is not data to be recorded in a programinformation file, VOLUME.TOC, ALBUM.STR or volume_write_protect_level,on the other hand, the recording operation is prohibited.

If the outcome of the judgment formed at the step S28 indicates thatvolume_write_protect_level is set at 6, the flow of the processingproceeds to a step S37 at which the CPU 21 forms a judgment as towhether or not the input data is data to be recorded in a stream file ora chunk-group information file. A value of volume_write_protect_levelequal to 6 indicates that the user is allowed to update only a streamfile, a chunk-group information file, a title information file, aprogram information file, VOLUME.TOC, ALBUM.STR andvolume_write_protect_level. Thus, if the outcome of the judgment formedat the step S37 indicates that the input data is data to be recorded ina stream file or a chunk-group information file, the flow of theprocessing proceeds to the step S30 at which the CPU 21 carries outprocessing to write the input data over existing data. If the outcome ofthe judgment formed at the step S37 indicates that the input data is notdata to be recorded in a stream file or a chunk-group information file,on the other hand, the flow of the processing proceeds to the step S36at which the CPU 21 carries out processing of this step and thesubsequent processing. To put it in detail, if the outcome of thejudgment formed at the step S36 indicates that the input data is data tobe recorded in a title information file, a program information file,VOLUME.TOC, ALBUM.STR or volume_write_protect_level itself, therecording operation is allowed, but if the outcome of the judgmentformed at the step S36 indicates that the input data is not data to berecorded in a title information file, a program information file,VOLUME.TOC, ALBUM.STR or volume_write_protect_level, on the other hand,the recording operation is prohibited.

If the outcome of the judgment formed at the step S28 indicates thatvolume_write_protect_level is not set at 6 either, on the other hand,the flow of the processing proceeds to a step S29 at which errorhandling is carried out. This is because volume_write_protect_level canbe set only at a value in the range 0 to 6 shown in FIG. 36. Thus, avalue of volume_write_protect_level in the range 7 to 15 not used forthe time being is an error which needs to be processed.

FIG. 40 is an explanatory diagram used for describing a relation ofvolume_write_protect_level. As shown in the figure, at each level, anoperation to update data of this level itself and data on the inner sideof this level, that is, data at a level represented by a value smallerthan a value for this level, is allowed. However, an operation to updatedata on the outer side of this level, that is, data at a levelrepresented by a value greater than the value for this level, isprohibited.

write_protect ( ) has been explained so far. Information on writeprotection similar to write_protect is also described in flags_for_titleand flags_for_program, on the basis of which similar processing iscarried out.

It should be noted that write protection is controlled in accordancewith the value of a logical sum of the setting position of thewrite-protect notch provided on the case of the optical disc 1 andpieces of information stored in write_protect ( ), flags_for_title andflags_for_program of VOLUME.TOC. To be more specific, prohibition ofprocessing to record data is implemented even if only one of themprescribes that a write operation is prohibited.

Next, play_protect ( ) shown in FIG. 8 is further explained. In thisplay_protect ( ), it is possible to set protect information to bereferred to in a playback operation for all titles or all programsrecorded in the optical disc 1. Protect information to be referred to ina playback operation for individual titles or individual programs isrecorded in flags_for_title of title_info ( ) shown in FIG. 16 or inflags_for_program of program shown in FIG. 18.

play_protect_length is an area used for recording a number expressingthe length of play_protect ( ) in terms of bytes.volume_play_protect_flag is an area used for recording a flagrepresenting protection status to be referred to in a playback operationfor the entire volume (the entire optical disc 1). As shown in FIG. 41,there are 4 types of status that can be set in the flag.

To be more specific, a value of 00 set in the flag indicates that anoperation to play back information from all titles and all programs isallowed. A value of 01 set in the flag indicates that an operation toplay back information from a program is allowed but an operation to playback information from a title is not. On the other hand, a value of 10set in the flag indicates that an operation to play back informationfrom a title is allowed but an operation to play back information from aprogram is not. Finally, a value of 11 set in the flag indicates that anoperation to play back information from all titles and all programs isprohibited.

password enable flag is a flag for indicating whetherpassword_for_volume_play_protect is valid or invalid.

expiration_time_enable_flag is a flag for indicating whetherplay_protect_expiration_time ( ) to be described later is valid orinvalid. If expiration_time_enable_flag indicates thatplay_protect_expiration_time ( ) is valid,password_for_volume_play_protect has a term of validity indicated byplay_protect_expiration_time ( ).

number_of_times_enable_flag is a flag for indicating whethernumber_of_times to be described later is valid or invalid.

password_for_volume_play_protect is an area used for recording apassword which is referred to when the level of a password or the termof validity is changed.

play_protect_set_time ( ) is an area used for recording a setting timein terms of years, months, days, hours, minutes and seconds which areeach expressed in the BCD format.

play_protect expiration_time ( ) is an area for recording a term ofvalidity in terms of years, months, days, hours, minutes and secondswhich are each expressed in the BCD format. A term of validity can beset for a password. When the term expires, the play_protect informationcan be changed without a password. An indefinite term can be set as aterm of validity.

number_of_times cited above is an area used for recording the number oftimes information has been recorded.

Next, processing to change play_protect is explained by referring to aflowchart shown in FIG. 42. As shown in the figure, the processingbegins with a step S51 at which the user enters a command to changeplay_protect by operating the input unit 14. The flow of the processingthen goes on to a step S52 at which the CPU 21 forms a judgment as towhether or not a predetermined password has been recorded inpassword_for_volume_play_protect in play_protect ( ) ofvolume_information ( ) in VOLUME.TOC stored in the RAM unit 24. If apassword has been recorded therein, the flow of the processing proceedsto a step S53 at which the CPU 21 forms a judgment as to whether or notplay_protect_expiration_time ( ) in play_protect ( ) is still valid atthe present time.

That is to say, the CPU 21 forms a judgment as to whether or not thepresent time is within a term of validity of the password which isrecorded in play_protect_expiration_time. If the outcome of the judgmentindicates that the password is valid, the flow of the processingcontinues to a step S54 at which the CPU 21 controls the OSD controlcircuit 9 to let a message be generated to request the user to enter apassword. The message is output through the synthesis circuit 8 and theoutput terminal P1 to be displayed on the display unit. The flow of theprocessing then goes on to a step S55 at which the user sees the messageand, in response to this message, the user enters a password byoperating the input unit 14.

Then, the flow of the processing proceeds to a step S56 at which the CPU21 forms a judgment as to whether or not the password entered by theuser at the step S55 is correct, that is, a judgment as to whether ornot the password entered by the user at the step S55 matches thepassword stored in password_for_volume play_protect. If the outcome ofthe judgment indicates that the entered password matches the storedpassword, the flow of the processing continues to a step S58 at whichthe CPU 21 controls the OSD control circuit 9 to let a message begenerated to indicate that the user is allowed to change play_protect.The message is output through the synthesis circuit 8 and the outputterminal P1 to be displayed on the display unit.

The flow of the processing then goes on to a step S59 at which the usersees the message and, in response to this message, the user entersinformation for changing play_protect by operating the input unit 14.After such information has been input, the flow of the processingproceeds to a step S60 at which the CPU 21 updates play_protect inaccordance with the input information. To put it in detail, the CPU 21updates the contents of play_protect stored in the RAM unit 24 andrecords the updated contents into the optical disc 1.

If the outcome of the judgment formed at the step S56 indicates that theentered password does not match the stored password, on the other hand,the flow of the processing continues to a step S57 at which the CPU 21controls the OSD control circuit 9 to let a message be generated anddisplayed on the display unit to indicate that the user is not allowedto change play_protect. In this case, the user is not allowed to changeplay_protect and the pieces of processing carried out at the steps S58to S60 are skipped.

If the outcome of the judgment formed at the step S52 indicates that novalid password has been recorded in password_for_volume_play_protect orthe outcome of the judgment formed at the step S53 indicates thatplay_protect_expiration_time ( ) in play_protect ( ) is not valid anymore at the present time, on the other hand, the flow of the processingproceeds to the step S58 at which the pieces of processing of the stepS58 and the subsequent steps are carried out. In this case, the user isallowed to update play_protect freely.

Next, a playback operation is explained by referring to a flowchartshown in FIG. 43. This processing is started when the user operates theinput unit 14 to enter a command to play back information from theoptical disc 1.

As shown in the figure, the processing begins with a step S71 at whichthe CPU 21 reads out volume_play_protect_flag stored in the RAM unit 24.This flag is included in play_protect ( ) of volume_information ( ) inVOLUME.TOC.

The flow of the processing then goes on to steps S72 to S75 at which theCPU 21 forms judgments as to whether volume_play_protect_flag read outat the step S71 has a value of 00, 01, 10 or 11 respectively.

To put it in detail, if the outcome of the judgment formed at the stepS72 indicates that volume_play_protect flag has a value of 00, the flowof the processing proceeds to a step S77 at which the CPU 21 carries outa playback operation in accordance with a command entered by the user.That is to say, since there is no restriction on the playback operation,the operation is carries out as specified by the command.

If the outcome of the judgment formed at the step S73 indicates thatvolume_play_protect_flag has a value of 01, the flow of the processingproceeds to a step S78 at which the CPU 21 forms a judgment as towhether or not the user has entered a command to request a playbackoperation of a title. If the command specifies a playback operation of atitle, the processing continues to a step S79 at which the CPU 21controls the OSD control circuit 9 to let a message be generated tonotify the user that a playback operation of a title is prohibited. Themessage is output through the synthesis circuit 8 and the outputterminal P1 to be displayed on the display unit.

If the outcome of the judgment indicates that the command does notspecify a playback operation of a title, on the other hand, theprocessing returns to the step S77 at which the CPU 21 carries out aplayback operation in accordance with the command entered by the user.For example, a playback operation of a program is carried out.

If the outcome of the judgment formed at the step S74 indicates thatvolume_play_protect_flag has a value of 10, the flow of the processingproceeds to a step S80 at which the CPU 21 forms a judgment as towhether or not the user has entered a command to request a playbackoperation of a program. If the command specifies a playback operation ofa program, the processing returns to the step S79 at which the CPU 21controls the OSD control circuit 9 to let a message be generated tonotify the user that a playback operation of a program is prohibited. Ifthe outcome of the judgment formed at the step S80 indicates that thecommand does not specify a playback operation of a program, for example,if the command specifies a playback operation of a title, on the otherhand, the processing returns to the step S77 at which the CPU 21 carriesout a playback operation in accordance with the command entered by theuser.

If the outcome of the judgment formed at the step S75 indicates thatvolume_play_protect_flag has a value of 11, the flow of the processingproceeds to a step S81 at which the CPU 21 forms a judgment as towhether or not the user has entered a command to request a playbackoperation of a title or a program. If the user has entered a command torequest a playback operation of a title or a program, the flow of theprocessing returns to the step S79 at which the CPU 21 lets a message begenerated to notify the user that the requested playback operation isprohibited. If the outcome of the judgment formed at the step S81indicates that the command does not specify a playback operation of atitle or a program, on the other hand, the processing returns to thestep S77 at which the CPU 21 carries out an operation to play back data.

If the outcome of the judgment formed at the step S75 indicates thatvolume_play_protect_flag does not have a value of 11, on the other hand,the flow of the processing proceeds to a step S76 at which the CPU 21carries out error processing. This is because, since the outcomes of thejudgments indicate that this flag has none of values of 00, 01, 10 and11, that is, the possible values for the flag, the error processingneeds to be carried out.

As described above, an operation to play back a title or a program iscontrolled in accordance with the value of volume_play_protect_flag.Even if a playback operation is prohibited by a value of the flag, witha password entered, however, the playback operation can be allowed. FIG.44 is a flowchart representing typical processing to allow a playbackoperation after checking an entered password even if the playbackoperation is prohibited by a value of the flag.

Pieces of processing carried out at steps S91 to S104 of the flowchartshown in FIG. 44 are basically the same as those of the steps S71 to S81of the flowchart shown in FIG. 43. If the outcome of a judgment formedat a step S98 corresponding to the step S78 of the flowchart shown inFIG. 43, a step S103 corresponding to a step S80 of the flowchart shownin FIG. 43 or a step S104 corresponding to the step S81 of the flowchartshown in FIG. 43 indicates that the requested operation to play backdata is prohibited by volume_play_protect_flag, the flow of theprocessing goes on to a step S99 at which the CPU 21 controls the OSDcontrol circuit 9 to let a message be generated and displayed in orderto request the user to enter a password. In response to the message, theuser enters a password by operating the input unit 14.

The flow of the processing then proceeds to a step S100 at which the CPU21 forms a judgment as to whether or not a password has been entered. Ifa password is found entered, the flow of the processing continues to astep S101 at which the CPU 21 forms a judgment as to whether or not theentered password is correct, that is, a judgment as to whether or notthe password entered by the user matches the password stored inpassword_for_volume_play_protect. If the outcome of the judgmentindicates that the entered password matches the stored password, theflow of the processing returns to a step S97 at which the CPU 21executes the requested operation to play back data in opposition to thevalue of volume_play_protect_flag.

If the outcome of the judgment formed at the step S101 indicates thatthe entered password is not correct, on the other hand, the flow of theprocessing goes on to a step S102 corresponding to the step S79 of theflowchart shown in FIG. 43. At the step S102, the CPU 21 controls theOSD control circuit 9 to let a message be generated and displayed on thedisplay unit in order to indicate that the requested playback operationis prohibited. In addition, also if the outcome of the judgment formedat the step S100 indicates that no password is entered, the message toindicate that the requested playback operation is prohibited isdisplayed.

The other processing is the same as that shown in FIG. 43.

Appropriate play-protect information can be recorded for a created oredited program. In this way, even if the user is allowed to freely playback titles individually, an operation to play back a program comprisinga plurality of titles to be reproduced in a predetermined order can beprohibited.

Next, volume_rating ( ) shown in FIG. 6 is further explained. Much likeplay_protect, rating is a means or a function to classify discs in orderto restrict operations to play back information from the discs. Onemethod of implementing the rating is the use of volume_rating ( ).volume_rating ( ) is information set to limit watchers and listeners ofall title or all programs recorded on the optical disc on the basis ofthe rating. Such information can also be set for each program or eachtitle. The rating is exemplified below by volume_rating ( ) which iseffective for all information recorded in the volume.

volume_rating_id is a descriptor used for showing that informationfollowing this descriptor is volume_rating ( ). volume_rating_length isan area used for recording the length of volume_rating ( ) expressed interms of bytes. volume_rating_type is an area used for recording a flagrepresenting a method of setting the rating. As shown in FIG. 45, thereare three types of rating method which can be selected.

To put it in detail, a value of 00 set in this flag indicates a ratingmethod whereby a judgment as to whether or not a watcher or a listeneris allowed to play back information is formed on the basis of the age ofthe watcher or the listener. A value of 01 set in this flag indicates arating method conforming to classification known as CARA established bythe MPAA (Motion Picture Association of America). A value of 10 set inthis flag indicates a rating method conforming to categorizationestablished by the RSAC (Recreational Software Advisory Council).

volume_rating_password is an area used for recording a password requiredin modifying information on volume_rating ( ).

With a value of 00 set in volume_rating_type, a judgment as to whetheror not a watcher or a listener is allowed to play back information isformed on the basis of the age of the watcher or the listener.country_code_for_rating is an area used for recording the code of acountry, that is, information indicating which country the rating isapplied to. age_for_volume_rating is an area used for recording an agelimit. A watcher or a listener having an age at least equal to the agelimit is allowed to watch or listen to video information recorded in avolume in which volume rating ( ) is recorded.

With a value of 01 set in volume_rating_type, a rating method conformingto the CARA classification is set for classifying work recorded in thevolume. Video information recorded in the volume is classified into 4categories shown in FIG. 46, namely, G, PG, PG-13 and NC17.CARA_category is an area used for recording a category of work recordedin the volume.

With a value of 10 set in volume_rating_type, a rating method conformingto the RSAC categorization is set for classifying work recorded in thevolume. RSAC_category is an area used for recording one of types ofcategorization shown in FIG. 47, namely, Violence Rating, Nudity Rating,Sex Rating and Language Rating. On the other hand, RSAC_level is an areaused for recording one of levels 0 to 4 shown in FIG. 48 for each typeof categorization.

Next, processing to set volume_rating is explained by referring to aflowchart shown in FIG. 49. As shown in the figure, the processingbegins with a step S111 at which the user enters a command to changevolume_rating by operating the input unit 14. The flow of the processingthen goes on to a step S112 at which the CPU 21 controls the OSD controlcircuit 9 to display a message urging the user to enter a passwordmatching that recorded in volume_rating_password. In response to themessage, the user enters a password by operating the input unit 14.

Then, the flow of the processing proceeds to a step S113 at which theCPU 21 forms a judgment as to whether or not the entered passwordmatches that recorded in volume_rating_password. If the entered passwordmatches that recorded in volume rating_password, the flow of theprocessing continues to a step S114 at which the CPU 21 controls the OSDcontrol circuit 9 to let a message be generated to notify the user thatvolume_rating can be changed. This message is output to the display unitby way of the synthesis circuit 8 and the output terminal P1 to bedisplayed thereon. Subsequently, the flow of the processing goes on to astep S114 to let the user select a value of volume_rating_type.

If the outcome of the judgment formed at the step S113 indicates thatthe entered password does not match that recorded involume_rating_password, on the other hand, the flow of the processingcontinues to a step S118 at which the CPU 21 controls the OSD controlcircuit 9 to let a message be generated and displayed on the displayunit to notify the user that modification of volume_rating isprohibited. In this case, the pieces of processing carried out at thesteps S114 to S117 are skipped and the user is not allowed to update thevalue of volume_rating.

The flow of the processing then goes on from the step S114 to a stepS115 at which the CPU 21 forms a judgment as to whether or not the valueof volume_rating type entered by the user is age limited. If the valueof volume_rating_type is age_limited, the flow of the processing goes onto a step S119 at which the CPU 21 controls the OSD control circuit 9 togenerate and display to the user an inquiry about a minimum age forlimiting the age of a watcher or a listener who will be allowed to playback information recorded on the optical disc. In response to thisinquiry, the user enters a command specifying a minimum age allowed towatch and listen to information played back from the volume by operatingthe input unit 14. The CPU 21 then sets age_for_volume_rating for thecommand entered by the user and further sets country_code_for_rating aswell. After the processing described above has been completed, the flowproceeds to a step S123.

If the outcome of the judgment formed at the step S115 indicates thatthe value of volume_rating_type is not age_limited, on the other hand,the flow of the processing goes on to a step S116 at which the CPU 21forms a judgment as to whether or not the value of volume_rating_typeentered by the user is CARA. If the value of volume_rating_type is CARA,the flow of the processing continues to a step S120 at which the CPU 21controls the OSD control circuit 9 to generate and display to the useran inquiry about a category to be set. In response to this inquiry, theuser enters a command specifying a CARA category by operating the inputunit 14. The CPU 21 then sets CARA_category in accordance with thecommand entered by the user. After the processing described above hasbeen completed, the flow proceeds to the step S123.

If the outcome of the judgment formed at the step S116 indicates thatthe value of volume_rating_type is not CARA, on the other hand, the flowof the processing goes on to a step S117 at which the CPU 21 forms ajudgment as to whether or not the value of volume_rating_type entered bythe user is RSAC. If the value of volume_rating_type is RSAC, the flowof the processing continues to a step S121 at which the CPU 21 controlsthe OSD control circuit 9 to generate and display to the user an inquiryabout which category defined by the RSAC is to be set. In response tothis inquiry, the user enters a command specifying an RSAC category byoperating the input unit 14. The CPU 21 then sets RSAC_category inaccordance with the command entered by the user. Subsequently, the flowof the processing continues to a step S122 at which the CPU 21 controlsthe OSD control circuit 9 to generate and display to the user an inquiryabout which level defined by the RSAC is to be set. In response to thisinquiry, the user enters a command specifying an RSAC level by operatingthe input unit 14. The CPU 21 then sets RSAC_level in accordance withthe command entered by the user. After the processing described abovehas been completed, the flow proceeds to the step S123.

At the step S123, the CPU 21 controls the OSD control circuit 9 togenerate and display to the user an inquiry about whether or notvolume_rating_password is to be modified. If the user enters YES byoperating the input unit 14 in response to the inquiry, the flow of theprocessing goes on to a step S124 at which the CPU 21 controls the OSDcontrol circuit 9 to display a message urging the user to enter a newpassword. In response to the message, the user enters a new password byoperating the input unit 14. The CPU 21 then replaces a passwordrecorded in volume_rating password with the new one. If the user entersNO by operating the input unit 14 in response to the inquiry issued atthe step S123, on the other hand, volume_rating_password is not changedand the processing to modify volume_rating is finished.

If the outcome of the judgment formed at the step S117 indicates thatthe value of volume_rating_type is not RSAC either, on the other hand,the flow of the processing goes on to a step S118 at which the CPU 21carries out error handling. This is because the value ofvolume_rating_type is limited to age limited, CARA and RSAC only. If thevalue of volume_rating type is determined to be none of them, errorhandling needs to be carried out.

Next, rating processing carried out during a playback operation isexplained by referring to a flowchart shown in FIGS. 50 and 51. Thisrating processing is started by the CPU 21 along with other processingwhen the user inserts an optical disc 1 into an optical-disc apparatus.As shown in FIG. 50, the rating processing begins with a step S131 atwhich the CPU 21 reads in volume_rating ( ) recorded on the optical disc1. To put in detail, the CPU 21 controls the optical head 2, playingback data from the optical disc 1. The data played back from the opticaldisc 1 is supplied to the read-in channel buffer 6 by way of the opticalhead 2, the RF & demodulation/modulation circuit 3, the ECC circuit 4and the switch 5 to be once stored in the buffer 6. The data stored inthe read-in channel buffer 6 is then transferred to the RAM unit 24. TheCPU 21 finally reads in volume_rating ( ) from the data stored in theRAM unit 24.

The flow of the processing then goes on to a step S132 at which the CPU21 forms a judgment as to whether or not the value of volume_rating_typeincluded in volume_rating ( ) is age_limited. If the value ofvolume_rating_type included in volume_rating ( ) is age_limited, theflow of the processing proceeds to a step S136. At the step S136, theCPU 21 reads in country codes from country_code_for_rating and values ofage_for_volume_rating included in volume_rating ( ) and selects a valueof age_for_volume_rating for a country code set on the optical-discapparatus. The flow of the processing then continues to a step S137 atwhich the CPU 21 compares an age limit set in the optical-disc apparatusspecifying the minimum age allowed to watch and listen to informationplayed back from the optical disc 1 with the selected value ofage_for_volume_rating. Then, the flow of the processing goes on to astep S142 to form a judgment as to whether or not an operation to playback information from the optical disc 1 is allowed for the age limitset in the optical-disc apparatus. If an operation to play backinformation from the optical disc 1 is allowed, the flow of theprocessing proceeds to a step S146. If the outcome of the judgment onthe age limit set in the optical-disc apparatus indicates that the useris not allowed to play back information from the optical disc 1, on theother hand, the flow of the processing continues to a step S145 todisplay a message stating that a playback operation is prohibited andterminate the playback processing.

If the outcome of the judgment formed at the step S132 indicates thatthe value of volume_rating_type included in volume_rating ( ) is not agelimited, on the other hand, the flow of the processing proceeds to astep S133.

At the step S133, the CPU 21 forms a judgment as to whether or not thevalue of volume_rating_type included in volume_rating ( ) is CARA. Ifthe value of volume_rating_type included in volume_rating ( ) is CARA,the flow of the processing goes on to a step S138. At the step S138, theCPU 21 reads in CARA_category of volume_rating ( ). The flow of theprocessing then proceeds to a step S139 at which the CPU 21 comparesCARA_category of volume_rating ( ) with a CARA category set in theoptical-disc apparatus. Then, the flow of the processing goes on to astep S143 to form a judgment as to whether or not an operation to playback information from the optical disc 1 is allowed for the CARAcategory set in the optical-disc apparatus. If an operation to play backinformation from the optical disc 1 is allowed, the flow of theprocessing proceeds to the step S146. If the outcome of the judgment onthe CARA category set in the optical-disc apparatus indicates that theuser is not allowed to play back information from the optical disc 1, onthe other hand, the flow of the processing continues to the step S145 todisplay a message stating that a playback operation is prohibited andterminate the playback processing.

If the outcome of the judgment formed at the step S133 indicates thatthe value of volume_rating_type included in volume_rating ( ) is notCARA, on the other hand, the flow of the processing proceeds to a stepS134. At the step S134, the CPU 21 forms a judgment as to whether or notthe value of volume_rating_type included in volume_rating ( ) is RSAC.If the value of volume_rating_type included in volume_rating ( ) isRSAC, the flow of the processing goes on to a step S140. At the stepS140, the CPU 21 reads in RSAC_category and RSAC_level of volume_rating( ). The flow of the processing then proceeds to a step S141 at whichthe CPU 21 compares RSAC_category and RSAC_level of volume_rating ( )respectively with a CARA category and a CARA level set in theoptical-disc apparatus. Then, the flow of the processing goes on to astep S144 to form a judgment as to whether or not an operation to playback information from the optical disc 1 is allowed for the RSACcategory and the RSAC level set in the optical-disc apparatus. If anoperation to play back information from the optical disc 1 is allowed,the flow of the processing proceeds to the step S146. If the outcome ofthe judgment on the RSAC category and the RSAC level set in theoptical-disc apparatus indicates that the user is not allowed to playback information from the optical disc 1, on the other hand, the flow ofthe processing continues to the step S145 to display a message statingthat a playback operation is prohibited and terminate the playbackprocessing.

If the outcome of the judgment formed at the step S134 indicates thatthe value of volume_rating_type included in volume_rating ( ) is notRSAC either, on the other hand, the flow of the processing proceeds to astep S135 at which error handing is carried out much like the step S118of the flowchart shown in FIG. 49.

Much like the processing shown in FIGS. 43 and 44, at the step S146,volume_play_protect_flag is checked. That is to say, when the rating isadded to play_protect as a function to restrict playback operations, therating is checked prior to the processing shown in FIGS. 43 and 44. Aspecified title or a specified program can not be played back from theoptical disc 1 unless the results of judgments on the rating andplay_protect indicate that a playback operation is allowed. In otherwords, if an outcome of a judgment formed in the processing to determinewhether or not a playback operation is allowed on the basis of therating or play_protect indicates that the playback operation isprohibited, an operation to play back a specified title or a specifiedprogram is not allowed.

Then, the flow of the processing goes on to a step S147. Also much likethe processing shown in FIGS. 43 and 44, at the step S147, the CPU 21forms a judgment as to whether an operation to play back informationfrom the optical disc 1 is allowed or prohibited. If the outcome of thejudgment on play_protect indicates a prohibited playback operation, theflow of the processing proceeds to the step S145. If the outcome of thejudgment on play_protect indicates an allowed playback operation, on theother hand, the flow of the processing proceeds to the step S148.

At the step S148, a specified title or a specified program is playedback without any further verification of protection because the title orthe program has been finally judged to be information that is allowed tobe played back.

As described above, the present invention is applied to an optical-discapparatus. However, the present invention can also be applied tooperations to record and play back information into and from a recordingmedium other than an optical disc.

It should be noted that, as a presentation medium for presentingcomputer programs to be executed to carry out the processing describedabove to the user, communication media such as a network and a satellitecan be utilized in addition to recording media like a magnetic disc, aCD-ROM and a solid-state memory device.

In the recording apparatus, the recording method, the presentationmedium and the recording medium according to the present invention,prohibition of a write operation over a combination of pieces of data isspecified. As a result, operatability of the recording apparatus can beimproved.

In the recording/playback apparatus, the recording/playback method andthe presentation medium according to the present invention, specifyinginformation stating prohibition of an overwrite operation for acombination of pieces of data is recorded into a recording medium, thespecifying information for a piece of data subjected to a recordingoperation in accordance with a command is played back from the recordingmedium, and an operation to record the piece of data into the recordingmedium is controlled in accordance with a result of a judgment formed onthe specifying information played back from the recording medium.

As a result, operatability of the recording/playback apparatus forrecording and playing back data can be improved.

In the playback apparatus, the recording playback method and thepresentation medium according to the present invention, an operation toplay back data from a recording medium is controlled in accordance witha prescribed regulation as to whether or not the operation to play backthe data recorded in the recording medium is allowed. As a result, aperson recording data is capable of controlling an operation to playback the data.

A recording medium according to the present invention is also used forrecording specifying information for specifying whether or not anoperation to play back the data is prohibited. As a result, it ispossible to provide a recording medium that allows a person recordingdata to control an operation to play back the data from the medium.

In the recording apparatus, the recording method and the presentationmedium according to the present invention, a prescribed regulation as towhether or not to prohibit an operation to play back data recorded in arecording medium is recorded in the recording medium. As a result, it ispossible to provide a recording medium that allows a person recordingdata to control an operation to play back the data from the medium.

In the recording/playback apparatus, the recording/playback method andthe presentation medium according to the present invention, specifyinginformation specifying whether or not to prohibit an operation to playback data recorded in a recording medium is recorded into the recordingmedium, the specifying information for data subjected to a playbackoperation in accordance with a command is played back from the recordingmedium, and an operation to play back data from the recording medium iscontrolled in accordance with a result of a judgment formed on thespecifying information played back from the recording medium.

As a result, a person recording data is capable of controlling anoperation to play back the data from the recording medium with a highdegree of reliability.

What is claimed is:
 1. A recording medium having recorded thereon aplurality of data units as well as specifying information for specifyingthat a write operation over data units of a first type is permittedwhile a write operation over data units of a second type is prohibited.2. The recording medium of claim 1, wherein each of said data units of asecond type is a combination of said data units of a first type.
 3. Therecording medium of claim 1, wherein said data units of a first type areeach files of a first type, and said data units of a second type arefiles that are each a combination of said files of a first type.
 4. Therecording medium of claim 1, further having recorded thereon specifyinginformation specifying a term of validity of each prohibition of a writeoperation.
 5. A recording/playback apparatus for recording and playingback a plurality of data units into and from a recording medium, saidrecording/playback apparatus comprising: recording means for recordingspecifying information for specifying that a write operation over dataunits of a first type is permitted while a write operation over dataunits of a second type is prohibited; playback means for playing backsaid specifying information for a data unit subjected to a recordingoperation in accordance with a command; and control means forcontrolling an operation to record data units into said recording mediumin accordance with the specifying information played back by saidplayback means.
 6. The recording/playback apparatus of claim 5, whereineach of said data units of a second type is a combination of said dataunits of a first type.
 7. The recording/playback apparatus of claim 5,wherein said data units of a first type are each files of a first type,and said data units of a second type are files that are each acombination of said files of a first type.
 8. The recording/playbackapparatus of claim 5, wherein said recording means further recordsspecifying information that specifies a term of validity of eachprohibition of a write operation, and said control means controls saidoperation to record data units further in accordance with said term ofvalidity.
 9. A recording/playback method for use in a recording/playbackapparatus for recording and playing back a plurality of data units intoand from a recording medium, said recording/playback method comprisingthe steps of: recording specifying information for specifying that awrite operation over data units of a first type is permitted while awrite operation over data units of a second type is prohibited; playingback said specifying information for a data unit subjected to arecording operation in accordance with a command; and controlling anoperation to record data units into said recording medium in accordancewith the specifying information played back in said playing back step.10. The recording/playback method of claim 9, wherein each of said dataunits of a second type is a combination of said data units of a firsttype.
 11. The recording/playback method of claim 9, wherein said dataunits of a first type are each files of a first type, and said dataunits of a second type are files that are each a combination of saidfiles of a first type.
 12. The recording/playback method of claim 9,further comprising: recording specifying information that specifies aterm of validity of each prohibition of a write operation; and inresponse to a command to perform a recording operation for subsequentdata units, overwriting a recorded data unit if said term of validitytherefor has expired, and preventing overwriting of said recorded dataunit if said term of validity has not yet expired.
 13. A presentationmedium for-presenting a program readable by a computer for execution tocause a recording/playback apparatus for recording and playing back aplurality of data units into and from a recording medium to carry outprocessing comprising the steps of: recording specifying information forspecifying that a write operation over data units of a first type ispermitted while a write operation over data units of a second type isprohibited; playing back said specifying information for a data unitsubjected to a recording operation in accordance with a command; andcontrolling an operation to record data units into said recording mediumin accordance with the specifying information played back in saidplaying back step.
 14. The presentation medium of claim 13, wherein eachof said data units of a second type is a combination of said data unitsof a first type.
 15. The presentation medium of claim 13, wherein saiddata units of a first type are each files of a first type, and said dataunits of a second type are files that are each a combination of saidfiles of a first type.
 16. The presentation medium of claim 13, whereinsaid processing further comprises the steps of: recording specifyinginformation specifying a term of validity of each prohibition of a writeoperation; and in response to a command to perform a recording operationfor subsequent data units, overwriting a recorded data unit if said termof validity therefor has expired, and preventing overwriting of saidrecorded data it if said term of validity has not yet expired.
 17. Arecording apparatus for recording data into a recording medium, saidrecording apparatus comprising: specifying means for specifying whetheror not an operation to play back individual data units from saidrecording medium is allowed while an operation to play back apredetermined combination of said data units is prohibited; andrecording means for recording what is specified by said specifying meansinto said recording medium.
 18. The recording apparatus of claim 17,wherein said specifying means further specifies a term of validity of aplayback prohibition.
 19. A recording method for use in a recordingapparatus for recording data into a recording medium, said recordingmethod comprising the steps of: specifying whether or not an operationto play back individual data units from said recording medium is allowedwhile an operation to play back a predetermined combination of said dataunits is prohibited; and recording what is specified at said specifyingstep onto said recording medium.
 20. The recording method of claim 19,further comprising specifying a term of validity of a playbackprohibition and recording said term of validity onto said recordingmedium.
 21. A presentation medium for presenting a program readable by acomputer for execution to cause a recording apparatus for recording dataonto a recording medium to carry out processing comprising the step of:specifying whether or not an operation to play back individual dataunits from said recording medium is allowed while an operation to playback a predetermined combination of said data units is prohibited; andrecording what is specified at said specifying step onto said recordingmedium.
 22. The presentation medium of claim 21, wherein said processingfurther comprises specifying a term of validity of a playbackprohibition and recording said term of validity onto said recordingmedium.
 23. A recording/playback apparatus for recording and playingback data into and from a recording medium, said recording/playbackapparatus comprising: recording means for recording specifyinginformation that specifies whether or not an operation to play backindividual data units from said recording medium is allowed while anoperation to play back a predetermined combination of said data units isprohibited; and playback means for playing back said specifyinginformation for data subjected to a playback operation in accordancewith a command; and control means for controlling an operation to playback data from said recording medium in accordance with the specifyinginformation played back by said playback means.
 24. Therecording/playback apparatus of claim 23, wherein said recording meansfurther records a term of validity of a playback prohibition, and saidcontrol means controls the operation to playback data from saidrecording medium further in accordance with said term of validity whichis played back by said playback means.
 25. A recording/playback methodfor use in a recording/playback apparatus for recording and playing backdata into and from a recording medium, said recording/playback methodcomprising: recording specifying information that specifies whether ornot an operation to play back individual data units from said recordingmedium is allowed while an operation to play back a predeterminedcombination of said data units is prohibited; and playing back saidspecifying information for data subjected to a playback operation inaccordance with a command; and controlling an operation to play backdata from said recording medium in accordance with the specifyinginformation played back by said playback means.
 26. Therecording/playback method of claim 25, wherein said processing furthercomprises recording a term of validity of a playback prohibition,playing back said term of validity, and said controlling said operationto play back data from said recording medium further in accordance withsaid played back term of validity.
 27. A presentation medium forpresenting a program readable by a computer for execution to cause arecording/playback apparatus for recording and playing back data intoand from a recording medium to carry out processing comprising the stepsof: recording specifying information that specifies whether or not anoperation to play back individual data units from said recording mediumis allowed while an operation to play back a predetermined combinationof said data units is prohibited; playing back said specifyinginformation for data subjected to a playback operation in accordancewith a command; and controlling an operation to play back data from saidrecording medium in accordance with the specifying information playedback by said playback means.
 28. The presentation medium of claim 27,wherein said processing further comprises recording a term of validityof a playback prohibition, playing back said term of validity, and saidcontrolling said operation to play back data from said recording mediumfurther in accordance with said played back term of validity.
 29. Arecording method for recording a plurality of data units onto arecording medium, comprising the steps of: specifying that a writeoperation over at least one of said data units is prohibited; specifyinga term of validity of each prohibition of a write operation; andrecording said specified write operation prohibition and term ofvalidity on said recording medium along with said data units.
 30. Arecording apparatus for recording a plurality of data streams on arecording medium, comprising: a recording unit for recording a datastream and playback control information designating a predeterminedsegment selected from the data stream or the connection of a pluralityof data streams on the recording medium; a reproduction unit forreproducing additional information indicative of whether overwritingand/or deletion of each playback control information is permitted or notfrom the recording medium; and a controller for controlling theoverwriting and or deletion of the playback control informationaccording to said additional information.
 31. The recording apparatus ofclaim 30, further comprising: a user interface for inputting a password;wherein said controller controls overwriting of the additionalinformation according to certification results of the input password.32. The recording apparatus of claim 30, wherein said controller permitsthe overwriting and/or deletion of the playback control information andprohibits the overwriting of the data stream according to the additionalinformation.
 33. The recording apparatus of claim 30, wherein when auser tries to overwrite and/or delete the playback control informationbeing prohibited, the controller controls an onscreen display controlcircuit to provide an alarm presentation to the user.
 34. A recordingmethod for recording a plurality of data streams on a recording medium,comprising the steps of: recording a data stream and playback controlinformation designating a predetermined segment selected from the datastream or the connection of a plurality of data streams on the recordingmedium; reproducing additional information indicative of whetheroverwriting and/or deletion of each playback control information ispermitted or not from the recording medium; and controlling theoverwriting and/or deletion of the playback control informationaccording to said additional information.
 35. The recording method ofclaim 34, further comprising: inputting a password via user interface;wherein overwriting of the additional information is controlledaccording to certification results of the input password.
 36. Therecording method of claim 34, wherein said controlling permits theoverwriting and/or deletion of the playback control information andprohibits the overwriting of the data stream according to the additionalinformation.
 37. The recording method of claim 34, wherein when a usertries to overwrite and/or delete the playback control information beingprohibited, an onscreen alarm is presented to the user.
 38. Apresentation medium for presenting a program readable by a computer forexecution to cause a recording apparatus for recording data onto arecording medium to carry out processing comprising the steps of:recording a data stream and playback control information designating apredetermined segment selected from the data stream or the connection ofa plurality of data streams on the recording medium; reproducingadditional information indicative of whether overwriting and/or deletionof each playback control information is permitted or not from therecording medium; and controlling the overwriting and/or deletion of theplayback control information according to said additional information.39. The presentation medium of claim 38, wherein said processing furthercomprises: inputting a password via a user interface; whereinoverwriting of the additional information is controlled according tocertification results of the input password.
 40. The presentation mediumof claim 38, wherein the processing permits the overwriting and/ordeletion of the playback control information and prohibits theoverwriting of the data stream according to the additional information.41. The presentation medium of claim 38, wherein the processing causesan onscreen alarm to be presented to a user when the user tries tooverwrite and/or delete the playback control information beingprohibited.
 42. A recording medium readable by a machine, said recordingmedium having recorded thereon: a plurality of data streams; playbackcontrol information designating a predetermined segment selected from arespective one of said data streams or the connection of a plurality ofsaid data streams on the recording medium; and additional informationindicative of whether or not overwriting and/or deletion of eachplayback control information is permitted from the recording medium. 43.The recording medium of claim 42, wherein when a user inputs a passwordvia a user interface of said machine, overwriting of the additionalinformation is controlled according to certification results of theinput password.
 44. The recording medium of claim 42, wherein theoverwriting and/or deletion of the playback control information ispermitted whilst the overwriting of the data stream according to theadditional information is prohibited.
 45. The recording medium of claim42, wherein the machine causes an onscreen alarm to be presented to userwhen the user tries to overwrite and/or delete the playback controlinformation being prohibited.
 46. A reproducing apparatus forreproducing data streams from a recording medium, comprising: areproducing unit for reproducing a data stream, playback controlinformation designating a predetermined segment selected from the datastream or the connection of a plurality of data streams, and additionalinformation indicative of whether overwriting and/or deletion of eachplayback control information is permitted or not from the recordingmedium; and a controller for controlling the reproduction of the datastream designated by the playback control information according to saidadditional information.
 47. The reproducing apparatus of claim 46,further comprising: a user interface for inputting a password; whereinsaid controller controls the reproduction of the data stream designatedby the playback control information according to a certification of saidpassword.
 48. The reproducing apparatus of claim 46, wherein when a usertries to play the data stream designated by the playback controlinformation being prohibited, the controller controls an onscreendisplay control circuit to provide an alarm presentation to the user.49. A reproducing method for reproducing data streams from a recordingmedium, comprising: reproducing a data stream, playback controlinformation designating a predetermined segment selected from the datastream or the connection of a plurality of data streams, and additionalinformation indicative of whether overwriting and/or deletion of eachplayback control information is permitted or not from the recordingmedium; and controlling the reproduction of the data stream designatedby the playback control information according to said additionalinformation.
 50. The reproducing method of claim 49, further comprising:inputting a password via a user interface; wherein the reproduction ofthe data stream designated by the playback control information iscontrolled according to a certification of said password.
 51. Thereproducing method of claim 49, wherein when a user tries to play thedata stream designated by the playback control information beingprohibited, an onscreen alarm is presented to the user.
 52. Apresentation medium for presenting a program readable by a computer forexecution to cause a reproducing apparatus for reproducing data from arecording medium to carry out processing comprising the steps of:reproducing a data stream, playback control information designating apredetermined segment selected from the data stream or the connection ofa plurality of data streams, and additional information indicative ofwhether overwriting and/or deletion of each playback control informationis permitted or not from the recording medium; and controlling thereproduction of the data stream designated by the playback controlinformation according to said additional information.
 53. Thepresentation medium of claim 52, wherein said processing furthercomprises reading an input password inputted via a user interface;wherein the reproduction of the data stream designated by the playbackcontrol information is controlled according to a certification of saidpassword.
 54. The presentation medium of claim 52, wherein when a usertries to play the data stream designated by the layback controlinformation being prohibited, said processing causes an onscreen alarmto be presented to the user.